Raphael was the only one who saw it happen in any detail. They'd all been so busy with their own battles. Donatello seemed to be holding his own, doing better than his brothers even. That's what made it so crazy.

Don had dodged out of the way of a giant stone fist. The punch was so intense that it cracked the solid earth beneath it. Don stayed low as he skidded away, his gaze intensifying like it always did when he was deep in concentration. He recovered from his skid, using one hand to control its direction. His muscles coiled and he used his bo to vault upwards, landing on his enemy's shoulder, 15 feet in the air. He stabbed out with his bo, taking aim at something shining in the stone giant's chest - something that had previously gone unnoticed.

"These medallions," he shouted to his brothers below. "That's what's allowing them to keep reanimating!" Don jumped as the giant tried to swipe him away, twisting in the air and landing adeptly on its other shoulder. He stabbed out with his might, and the amulet broke free. Don leaped down and landed on the ground gracefully, spinning to watch his opponent fall. That was really where he made his biggest mistake, spinning instead of leaping away or simply hitting the deck.

The turtles had been fighting for 15 hard minutes and managed to take a few giants down during that time. Each time, they fell straight down to the earth, breaking upon contact, then reanimating moments afterward. Don couldn't have known that knocking out the amulet would've caused the stone creature to explode outwards into a hurricane of flying rocks. He couldn't have known, but he'd kick himself for years after for not being able to foresee it.

He'd spun because he had wanted to ensure that the beast didn't stumble in its fall, possibly threatening his brothers as they battled the other giants. He'd done what he thought made sense at the time. But it was stupid, so stupid.

Don landed and began a clockwise spin, preparing to spring up and land on top of the newly inanimate pile of rocks that should have been there. He swung his arms around ahead of him and set his bo in the ground, even before he finished turning, in one of his trademark lightning-fast moves. He planted his leading right leg and prepared to kick with his left, his powerful arm and shoulder muscles transferring all of his energy to his bo and that planted right leg, which was already holding the weight of his body, and straining to halt his spinning motion. His eyes widened as suddenly he realized that a series of boulders were flying through the air. One headed directly for his knee, only microseconds from hitting it.

Given how quickly Donatello's mind worked, he knew what was about to happen, but he was helpless to stop it. The boulder crashed directly into his kneecap and lower leg, causing it to buckle. Don could feel everything connecting his upper and lower leg rip apart. His knee and lower leg pitched backward with the rock. His upper body, still caught in that damn spin, twisted and pitched forward. The hyperextension was so severe that Don banged his chest against the rock.

Raphael saw it. He wished he didn't. It was the stuff of nightmares, even worse than those gruesome injuries that you see during football games - the ones that the telecasters refuse to show replays of. As sickening as it was, it was over in an instant. Don's upper body reversed direction and fell backward. The boulder rolled off of Don's leg and settled down beside him. Raph could see Don paw through the dirt to better shield himself next to the boulder. He saw how violently Don's hands were trembling when he reached out to correct his damaged limb's position before collapsing next to the chunk of rock that had just obliterated his life as he had known it in an instant.

"They explode when the medallions are removed!" Raphael hollered to Leonardo and Michelangelo. He tried to keep an eye on Donatello as he fought his own opponent. Don was lying still as death, his face tight, eyes squeezed shut. The only reason Raphael knew that he was conscious was that he could see Don's fingers digging into the ground as they, contorted in agony. Raphael wanted to reach Donnie's side, but he couldn't risk drawing the battle any closer to his downed brother.

Leonardo dared look over his shoulder as he fought two giants at once. "Where's Don?"

"He's down!" Raphael shouted, jumping away from a stone fist. "Hurt bad!"

To Raph's surprise, Don added, "Not dying," in a voice that sounded nothing like his own. Raph couldn't believe Don was able to talk at all.

"Stay down, Don," Leo ordered. "If these guys explode, we've got to fight them from a distance. Use your shuriken. Aim for the medallions!"

Donatello occasionally managed to open an eye. He watched as his brothers completed what he was fairly certain would be his final battle. He tried to stay awake and coherent, but his mind was in constant war with pain and shock that was threatening to overwhelm him.

Finally, Michelangelo came to his side, distressed to see how badly Don was trembling. "Where are you hurt?"

"Knee," Don gulped. "Right knee."

Mikey tentatively reached his hand out, intending to check for broken bones. Don didn't stop him. Mikey's touch was light as a feather, but it was still too much. "Don't!" Don hissed.

"Don, we're going to have to set it before we can move you," Mikey reasoned. The way Don's leg was twisted was all wrong. It was swollen and discolored already, and Mikey had noticed how warm it was. Not good.

"I know," Don whimpered. "But I can't…"

Mikey crawled towards Don's head and rubbed his shoulder. "I know," he soothed. "I know. We'll wait for Leo and Raph, get you something to bite down on."

"Okay," Don whispered. He reached out and weakly clasped Mikey's hand while they waited.

In the end, it took both Leo and Raph to hold Don still enough for Mikey to brace his knee. By then, Donatello was bordering upon incoherent.

Donatello passed out on the ride home, and Splinter administered a sedative to ensure that he stayed that way. It only took one look at Don's leg to know that an extended period of unconsciousness would be a mercy for the boy.

Leonardo rented a portable ultrasound to take a look at the damage, using the same methods than Don had used to rent the bedside X-ray for Raphael years before. Cruelly, it was necessary to wake Don prior to using it. The assembly and operating instructions were too complex for the rest of them, and Don was the only one who would know what he was looking at anyway. They cut off the sedatives but pumped as many painkillers as they could into the IV line that they had set up the night before.

Don whimpered and moaned for a good two hours before regaining consciousness. It was heartbreaking to hear those noises coming from him. Eventually, his eyes flickered open. Leonardo hated how dark and hazy they looked. "Donnie," he whispered.

Don's eyes wandered to his knee, then closed again. He was covered in several blankets to stave off shock, but the bulk of a heavy brace was visible through the layers of cotton-poly blend. "So that really happened," Don mumbled. "Damn." He lifted his trembling hand and pinched between his eyes. "Damn, damn."

"I'm sorry," Leo said. "It did. The good news is that we can't find any breaks, other than in your kneecap. The bad news is that the joint is twice its normal size and before we braced it, it was very... unstable."

"Yup," Don breathed. He could vaguely recall repositioning it on the battlefield. His lower leg had hardly seemed connected to his knee at all. He was lucky that the popliteal artery hadn't ruptured right then and there.

Leo sighed. "Don't try to move, by the way. We immobilized your knee, but we also lashed you to the bed for good measure."

"Okay," Don murmured. He hadn't been intending to move anyway. Not for a very long time. "How long was I out?"

"It's been about 20 hours," Leonardo explained. "We sedated you overnight. You were just in too much pain. How are you feeling now?"

"Foggy," Don answered. "How many painkillers am I on?"

"You're maxed out on morphine," Leo answered.

"That explains it."

"What's your pain level?"

Don thought about lying, but in the end, he answered honestly. "Eight."

Leo shook his head sadly and caressed Don's shoulder. "Okay. Well, at least you stopped shaking. That's something anyway."

Don closed his eyes. "Mmm."

"So listen, I know that this is a lot to ask of you right now, but we rented a portable ultrasound. Can you talk me through setting it up?" Leonardo requested.

"Hmm?"

"We can't… It's too complicated for us to set up. Can you help out?" Leo elaborated. "We'll do the work, run the scan."

"What scan?" Donatello murmured.

Leo frowned. Don had brain fog all right. "The scan we need to do of your knee."

"My knee?"

Leo took his brother's hand. "You hurt your knee, Don."

Don grimaced. "I know."

"We need to assess the damage, figure out how to fix it," Leonardo patiently explained.

Don closed his eyes, deciding whether he should allow himself to drift back into his drug-induced slumber. He didn't need to run any tests to know that he'd never use his knee again. He'd known that the second he saw that boulder closing in. Still, Leo had apparently already rented the scanner. He had taken the risk of going to the surface to pick it up. The daily rental fee was quite expensive. Not only that, but it would be good to see the damage, if for no other reason than to know for sure.

"Okay," Don breathed. "Please turn down my morphine drip a little. Can't focus very well."

"I don't think that's such a good idea," Leonardo warned.

"It's fine. I'll be fine. You can turn it back up when we're done."

It took a couple of hours of Leo and Don working together to get the scanner up and running. By then, Don was shaking again. Leo maxed out the drip once more, and let Don sleep off the worst of the pain before conducting the exam.

Don was poker-faced as he talked Leo through running the tests that confirmed all of his fears. Other than offering instructions and occasionally grunting in pain. He was quiet. Leo looked to Don when he turned off the machine. "Well?"

"Well, what?" Don asked.

"What do you think? How bad is the damage and how do we fix it?" Leonardo pressed.

Don hesitated. He didn't want to say the words, not right now. He wasn't used to feeling that anything was beyond hope. He was hurting, tired, not thinking clearly. "I need to do some research." That wasn't a lie. Not at all. It just wasn't the whole truth.

Don would've rolled over if he wasn't strapped down. "I'm tired, Leo. My knee hurts a lot. Can we talk in the morning?"

Don convalesced in his bedroom, remaining hooked up to a catheter and lashed to the bed for the better part of a week. His family never left his side. Occasionally, he would ask for his laptop so that he could do some research or at least go through the motions. Other than that, he just lied there. The painkillers made him sleepy.

And, those painkillers were about to become a problem.

"We're running low on morphine, Don," Leo announced gently one morning. "We can try to get more, but, I don't want you to grow dependent on the stuff. Do you have any thoughts about a long-term solution?"

"We can start weaning me off the morphine," Don considered. "I don't like how it affects me anyway. Let's cut the dosage in half, then keep reducing it by 50% each day."

"Okay. Then what do we do?" Leonardo asked.

"Nothing," Don replied. "I'll just take over the counter anti-inflammatory painkillers."

"Aren't you going to want something stronger, at least during your rehabilitation?" Leonardo fretted. He hadn't wanted to press Don, but he just assumed that there was something that they could be doing. Something that Don was still working on, and hadn't told them about yet.

Don winced. "There isn't any rehabilitation to be done. I just need to keep my knee immobilized."

"So, do you need me to rent the scanner again? See how your knee is healing up?" Leonardo inquired.

"You don't need to do that, Leo." Don sighed. "Could you get the guys? It's high time that I spoke to you all."

Leonardo didn't like the sound of that. He paused for a moment before getting up. "Sure thing, Don." He clasped Don's shoulder before fetching the rest of the family. Everyone filed in and sat around Don's bed.

"So, listen," Donatello started, looking bitterly unhappy. "My knee injury," he stopped for a long breath. "What you see is what you get. This is it for me."

"What do you mean?" Michelangelo asked, completely perplexed.

Raphael didn't need Don to elaborate. He'd suspected all along that there wouldn't be any coming back for Don.

"I can't." Don paused to consider his wording. "I'm not ever going to regain function in my leg."

"Do you mean full function?" Leonardo asked.

"I mean any function," Don clarified. "The damage is too severe. It can't be healed. My ninja days are over, guys. I'm sorry."

"But Don," Mikey pled. "You can fix anything. There's got to be something you can do!"

Donatello looked even sadder. "No. Without getting into the sordid biological details too much, my knee is completely destroyed. Several of the ligaments and tendons suffered nearly complete tears. The cartilage is severely torn as well, even the muscles. Stuff like that can't heal on its own. My knee won't work. It never will again."

"Could a doctor fix this?" Leonardo asked tentatively.

Don shrugged. "It'd probably be tricky. I'd need a total knee replacement, as well as some other supportive surgeries. It might be too far gone even for that. But, what's the point of daydreaming about doctors anyway? That's not the world that we live in."

"Maybe so," Mikey considered. "But even if you can't fix it, you can work around it, right? You could build a mech suit or some sort of bionic brace?"

"I doubt it," Don mourned. "I mean, I haven't been out of bed for a week, and even so, I'm still barely functional. Something like that would hurt like shell. I think that you guys just need to start considering yourselves a team of three. This is one thing I just can't fix. I'm sorry guys."

Raphael finally spoke. "Don, we can't go on as a team without you."

Don reached out for his hand. "Yes, you can. You don't need me."

"Yes, we do!" Leonardo insisted. "You're our tech guru, our long-range weapons expert, my chief strategist."

Don smiled sadly. "I can still build your vehicles and tech. Granted, it'll be a much slower process than it was before. I can make you guys body-cams so that I can see what you see on missions. I can still offer advice, be that voice in your ear when you need it. I just can't be beside you."

Don looked at his brothers' crestfallen faces. "I'm sorry. Believe me, I wish that it didn't have to be this way. I really do."

"We ought to be the ones comforting you," Raph remarked.

Don smiled a little, feeling close to tears. "I wouldn't say no to a gentle hug."

He got four of them.

It took a few more weeks for Don to convince the guys to make that first three-turtle patrol. Splinter didn't know what to expect when his healthy sons left. They had hardly wandered from Donatello's side, and he thought perhaps his genius son might need some time alone to process what had happened to him.

Nevertheless, Splinter was pleased to hear the sound of crutches approaching. Splinter helped Donatello settle down in the middle of the sofa, and cradled his leg on a pillow that had been set out on the coffee table. Splinter set Donatello's crutches nearby, while Donatello closed his eyes and breathed through the pain that came with every movement. Splinter was loathe to sit back down, for fear of jostling his son. Sensing this, Donatello pet the cushion beside him.

Splinter sat, and Don nestled a little closer, laying his head on his father's shoulder. "So, what do we do now?" Donatello asked quietly.

"We wait," Splinter answered, putting his arm around his son's shoulders. "And, hope for the best."

"I've always wondered how you did it," Donatello quietly confessed. "Sat down here and kept yourself from worrying."

"Usually I meditate or enjoy the peace of solitude," Splinter admitted.

Donatello made a humming noise. "I suppose you haven't had much of that lately, thanks to me."

"I welcome your company, Donatello. "Besides, I believe that, of all my sons, you have the most peaceful soul."

"Perhaps," Donatello considered. "I'm glad that if this had to happen to anyone, it was me. At least I still have my inventing, my research and projects. Imagine Leo without ninjitsu, or Raph not being able to play the part of family protector. Imagine Mikey cooped up down here with a physical handicap for the rest of his life."

"I hate to imagine that," Splinter agreed. "But I also hate to imagine you hampered by this for the rest of your life."

"True, but you've got to admit that I'm better equipped to handle this than the others," Don pressed.

"If you say so, Donatello."

"Mikey would have driven us bonkers by now." Don did his best Mikey impression. "My knee hurts. My knee hurts. My knee hurts. I'd rather deal with chronic pain then listen to that for the rest of my life."

When Splinter offered no reply, Donatello sighed and said in his own voice. "My knee hurts."

"I know, my son."

"It really stinks, you know? I try to tell myself how much worse it could have been. At least it was me, not one of them. At least I'm alive. At least I wasn't paralyzed. I didn't suffer brain damage. I didn't lose a limb." Don paused. "But, if I had just leaped away instead of spinning..."

"I know my son. But, you did what your instincts told you to do. You can't beat yourself up over this," Splinter preached.

"I know. I just didn't expect this," Don mused. "I mean, I always knew the risks that we were taking when we walked out the door. I always knew that I could die or be maimed. I always knew that my body would give out at some point in time. It's just that… I felt like I was in my prime, like there was so much left to do."

"But you have already done so much, Donatello," Splinter praised. "If you hadn't been able to contain those stone giants, they could have killed countless innocent people."

"My knee is a small price to pay when you think of it that way," Donatello conceded.

"Yes, and that was only one incident. Think of all the other adventures you have had, all the people that you helped."

"Think of all the others that I might have still helped. I wasn't ready to retire, Dad." Don realized what he had said. "Is it okay if I just call you Dad? Sensei is difficult for me right now. Reminds me too much of what I've lost."

"You may call me whatever you like, my son. But I think that you will find, in time, that you aren't quite as retired as you think you are. There may come a time that your brothers will need you. Then, I'm sure you would not hesitate to jump in and rescue them."

"Of course I would do that. It's just that… everyone always expects miracles from me, you know? Mikey was fully convinced that I would just build a bionic leg and go right back to being my old self. Leo just assumed that I'd find some magic cure. Sometimes, there's no miracle to be had. They've got to know that, right?" Donatello frowned miserably. "I'll always find a way to be there in an emergency, but at the moment, Mr. Fix It is out of ideas."

"That's okay, Donatello," Splinter soothed. "You can't solve every problem. Perhaps it is good that you are taking this time to rest and regroup."

"It's not like I have much choice. At the moment, the pain is still pretty debilitating. I'm hoping that my body will eventually adjust, but for now, it's all I can do just to keep it at bay. I sneezed the other day and almost passed out. It hurts when I laugh." Don let out a sharp breath before continuing. "Do you know what a kick in the teeth that is? Not much makes me laugh these days, but on the rare occasions that something actually does, I'm instantly reminded - brought back to earth. Why are you laughing when you're supposed to be suffering?"

Splinter held his son a little tighter. "My Donatello. I wish that I could take this pain from you. Both the mental and the physical."

Donatello smiled, despite the sadness in his eyes. "You do. You know, I won't deny that this past month has been… just terrible, but there have been some bright spots too. Having you guys around for me all the time, seeing how much you care, even when I can't offer anything in return, that's been nice."

Splinter considered his son. Out of all the turtles, Donatello had always been the quiet one, the gentle one. He wasn't obsessed with proving that he was the best, the strongest, the most fun. He was the most willing to beg for mercy to be granted to the enemy, even to show weakness himself. As a child, he had been more than willing to climb onto his father's lap for comfort, even if the others found it babyish and teased him for it. In his prime, he was so busy all the time. His work was lonely by its nature, but he made it a point to build his labs with open walls, to work on his projects in the living room while his brothers watched TV, at the kitchen table while they ate.

For the weeks that he was lashed to the bed, Donatello had never turned his family away. He never asked for privacy so that he could cry with no one seeing. He was never afraid to reach for someone's hand when the pain was at its worst. Donatello had clearly never intended to sequester himself away, but somehow it had happened anyway.

"For these past few years, I've been pulled in so many directions at once. One minute, I'm an elite ninja, the next, I'm an engineer, a mechanic, a scientist. There were times that it was hard to not lose myself in all of that - whatever I am at my core when you strip all of that other stuff away. So, as hard as this injury has been on me, I've got to admit that it feels sort of good to be just Donnie for a change."

Splinter was overcome with love for his child. "Donatello. What you are at your core has always been more than enough. The gifts you have given us, running water, heat, electricity, the vehicles, the gadgetry - everything; they have been wonderful. But, they pale in comparison to the gift of your mere presence."

"Speaking of my presence, I've always worried about you being all alone down here when we're gone," Don confessed. "At least I can keep a closer eye on you now. Maybe that's another bright spot."

Splinter's lips rose a little. "And yet, if I asked you to get me a glass of water?"

Don snickered, grabbing his knee as he did so. "I'd invite you to get it yourself. It's rather difficult to carry a glass of water while on crutches."

"We should start using bottled water," Splinter wisely assessed. "And perhaps obtain a service dog."

Don's eyes widened. "I'm not drinking from a water bottle that some dog has slobbered on. Besides, where would it do its business? What we need is a trained monkey."

Splinter leg out a hearty laugh. "Donatello, don't tell your brothers that I said this, but you always were the smart one."

There were a lot of things that Leo had begun to resent, and it grew worse and worse with each passing week. He couldn't stand the sight of Don's bulky knee immobilizer. He had assumed that it would be downgraded to a brace at some point, but apparently, Don intended to wear it forever. He hated that there were pillow-covered stools set up at all of Don's usually hangouts - under his computer table, in front of the chair that had been placed in the garage, next to the desk in his bedroom. He hated that Don sometimes moaned in his sleep, particularly on cold nights, or when the weather was changing. He hated hearing Don's voice in his earpiece when he'd much rather have his brother beside him. He resented the robot that Don was building to replace him on missions.

Leo particularly resented the damn hospital. It was right there, a few blocks away, taking in patients far less deserving than Donatello. Gang members sporting bullet wounds, burnouts who had overdosed for the third time that year, spoiled rich kids injured while partaking in over the top hobbies, drunk drivers who had crashed their cars - they all marched through the doors like it was nothing. But Donatello, who had only ever wanted to help people, whose only crime was spinning when he should have leaped, who lived with an incredible amount of pain that he hardly ever spoke of, who was apparently crippled for life- he could never go there. Leonardo hated it.

But, Leo could never hate or resent Donatello himself. His injury had slowed him down, but it hadn't broken him. He was still doing his best for his family. He was staying in shape as much as he could, pumping iron, exercising his good leg. He was still inventing, the new robot (or Don-bot, as they had taken to calling it) being his latest project. He had even obtained a work-from-home job, that provided them with ample pizza money.

Every night, after patrol, Leo would sit in Don's room and chat over a cup of herbal tea. Don had cut out coffee. He had enough trouble sleeping as it was. That was another thing that Leo resented - that Don had been denied even that simple pleasure. Leo liked to think that the nightly chats kept Don feeling like part of the team. He usually ended them by massaging Don's shoulders. That's where Don carried his stress, and being confined to the sewers, dealing with chronic pain, and pent up energy, and hobbling around on crutches all day was very stressful on the once-vigorous turtle. Leo wanted to do all that he could for his fallen brother.

And, to that end, the turtles began hanging around the hospital during patrols. Leo hoped that maybe they might save a doctor or a nurse, even a benefactor or member of the board. Maybe, they might feel obliged to then do the turtles a favor. Leo knew that it would take a lot more than luck and the generosity of strangers to fix Don, but he had to start somewhere.

And, muggings, assaults, and thefts did happen. When they did, Leo and the guys acted a little differently than normal. They came out of the shadows a little more. They wanted their faces to be known. In a few months' time, they'd become urban legends in that particular neighborhood.

After a slow night, the guys came home early. They found Don in the lab, working on his robot and listening to music. He had his leg propped up, as always, but tonight he was wearing a strange bundle of wires and electrodes around his arms and shoulders. Don turned with a wince and then smiled brightly. "Hey, guys! Watch this!"

Donatello waved, and the robot, which at this point was only a torso, perfectly mimicked the motion. It was amazing, the things that Don could do.

"Wow. How did you pull that off?" Michelangelo asked, impressed with how fluid the motion had been.

"It helps that I'm making enough money to order the parts that I need online, rather than scrounging through junkyards for whatever I can find," Donatello explained. "Hey Raph, try for a high three."

Raphael marched over, feeling like an idiot. He held up his hand, and the partially-built Don-bot slapped it. "Pretty impressive," Raph praised.

"And watch this," Don urged. He made a fist and swung. The robot's move was lightning fast and as powerful as Donatello's.

Leonardo whistled.

"So, what do you think?" Don asked. He gave a hopeful thumbs-up, and the robot did too.

"I think that you mastered the arms," Leo answered. "Do you have any plans for the rest of it?"

"I've been debating. There'll be a camera on the head that I'll be able to watch, and I'll remotely control the arms from here using the sensor-net. Obviously, I can only move one leg, so I'll have to do something different for the lower half. It could either roll on a ball, which I could shift using my torso, or I could attempt some sort of AI."

"AI, as in artificial intelligence?" Leonardo asked.

"Sure," Don replied. "But a very, very basic one. Something that could predict where I might want the robot to go, that could be easily overridden if it guessed wrong."

"I didn't know that you could do that," Leo mused.

"I can't," Don said. "Yet."

Later that week, as Leo was massaging Don's shoulders, Donatello stopped him by placing his hand over one of Leo's. "Hey," Don began. "Why have you been hanging around the hospital so much lately?"

"It's in a dangerous part of the City," Leonardo replied. "I'd rather protect the medical staff and recovering patients than get involved in random street fights and pointless gang wars."

"But why are you taking so many risks when you're there? From what I've seen on the body-cams, it's almost like you want to be noticed."

Leo clasped Donnie's shoulder a little tighter. "I don't like seeing you like this, Don."

"I'm fine," Don promised. "You shouldn't be taking risks on my account."

"You're not fine, Donnie," Leonardo countered. "You don't deserve to live like this."

"I can live with a bum knee. I can't live without the three of you. What if you get caught?"

"We won't," Leonardo insisted. "We're careful."

"What's your plan, anyway? What are you even aiming to do?" Don wondered.

"I don't know, exactly," Leo answered. "I just figure that it can't hurt to make a few well-placed friends."

"Leo, please just stop taking so many risks, especially if you don't have a plan. I doubt that any human doctor could fix me anyway. But, even if they could… the pain that I suffer is mine alone. I don't want you to bring any of it down upon yourselves, and potentially revealing our existence to the public could do just that."

Leonardo said something that he rarely ever did. "You're wrong, Donatello. Your suffering is not yours to bear alone, and it never has been. We all feel it every day. Patrols and training feel all wrong without you there. And the vehicles that you built seem so empty without you in them. When we're in the middle of one of those messes that we get ourselves into, I look to you for advice, only to find that you're not with us. Your voice in an earpiece just isn't the same. Raphael is so used to watching your back that even now, I still catch him frantically searching for you in the heat of battle. And Mikey… haven't you noticed how much he's toned it down around here? He told me that he knows it hurts you to laugh, so he tries not to make you do it."

Donatello let the sadness show in his brown eyes. "I didn't realize that you guys felt that way. I figured that you would have adjusted by now. I'm sorry."

Leonardo took his brother in his arms. "Don't be sorry. Just let us fight for you. Let us fight for you as hard as you've always fought for us."

Don nodded and hugged Leo back. "Okay, but just, don't do anything that might put your own lives at risk." He broke the hug and leaned back to look Leo in the eyes. "I mean it. Right now, I don't have a functional knee, but without you guys, I don't have a life. At least not one worth living."

Watching the hospital could be sad at times. Not all patients that went in came back out. Sometimes they left missing arms or legs. That certainly hit close to home for Leo. It was watching one of these patients that Leo suddenly had an idea. When he did, he wondered why he didn't think of it sooner.

"Hey, Don," Leo greeted as he handed his brother a cup of tea. "Did you ever think of the possible medical uses for the Don-bot technology?"

"Do you mean like using it as a prosthetic? Yes, I have. But, I haven't figured out a way to make an accurate neural interface." Don looked down at his cup. "As you know, I'm hardly a doctor."

"Perhaps not, but your robotics are so smooth. The way they perfectly mimic natural motion, control pressure, and speed, I don't think that any human technology even comes close to that," Leo praised.

"It's a robot. Not a prosthetic. Believe me, I'd love to use the technology to help people, but it's just not there yet." Don shrugged. "Maybe someday."

"Someday could come sooner than you think. Maybe we could provide this to a medical expert and see if they could develop the missing pieces," Leonardo suggested.

"Thank you. I am proud of the technology. But-" Don stopped talking when he realized what Leo was getting at. "You don't mean?"

"There's someone at the hospital who might find it interesting. A highly-placed someone, who might be willing to pay with an off-the-books surgery."

Don didn't want to allow himself to get too hopeful too fast. "Why would they do that, and agree to keep our secret?"

"Because there's profit to be had. They could make millions off of your designs. The person I have in mind may have some personal reasons as well," Leonardo answered. "I could give them a little demo, only hand it over after the surgery is complete."

Donatello thought about it. "Maybe I ought to put a couple more fingers on this thing."

It was Michelangelo who actually brokered the deal, being the friendliest turtle in the group. Don stayed home, trying not to be nervous. He didn't even watch on the body-cam feed. Michelangelo waited for the target, then began to move. Leo and Raph were flanking him on either side.

"Dr. Modha?" Mikey said tentatively, stepping out of a dark corner within the parking garage.

The woman was startled but didn't scream or run. She knew better, after her first encounter. "You again," she said. "I guess that I never got the chance to properly thank you for stopping that mugger."

"No problem. It's kind of our thing. Name's Michelangelo. That's Leonardo to the left, and Raphael to the right." Mikey stuck out his hand.

The woman shook it, not appearing repulsed at all. "Uh, hello Michelangelo. Apparently, you already know my name. Am I in some sort of trouble?"

"No. We have a proposal for you, but we'll make it quick. As you know, we like to keep a low profile," Leo spoke up.

"I do. My colleagues all said that I was crazy until they began catching glimpses of you as well."

"Well, we have something even more impressive to show you," Michelangelo said.

Raphael handed Mikey the arm, which Don had mounted to a piece of particleboard. Leo was wearing the electrodes that controlled the arm. Don's tech had come a long way. Just like Don had done that first time, Leo waved. He hoped that Dr. Modha would be as impressed as he was.

The doctor tilted her head. "Where did you get this?"

"My brother Donatello built it," Michelangelo explained. "He's kind of a whiz with stuff like this."

"Ask it to do something," Leo requested.

"Snap its fingers," Dr. Modha instructed.

Leo did just that. Of course, the hand made no noise. Nevertheless, the doctor seemed impressed. She stepped closer to the arm. "Mimic me," she said. Leo attempted to do just that. For a few minutes, the two rolled their wrists and elbows, opened and closed their hands, and wriggled specific fingers. The last part was a little hard for Leo since he had 3 and the bot had 5, but that's where Don's AI came in. It did a pretty good job of predicting what moves to make.

"Fascinating," Dr. Modha said, finally stepping away. "You said that your brother built this?"

"Yes. Donatello," Mikey confirmed.

"And why are you showing it to me?" the doctor asked.

"We thought maybe it could help people. We're kind of into that sort of thing," Michelangelo answered. "Don thought it could be useful as a prosthetic, but he can't build the neural interface on his own."

Dr. Modha looked at him. "And you think that I can?"

"We hope so," Michelangelo replied.

"This technology could make you rich, you know. Why would you just hand it over?" she asked.

"We're not, to be clear," Michelangelo said, trying to sound gentle. "We'd be asking you to do us a favor before we hand it over."

"And, what favor might that be?"

"Our brother, Donatello, the one who built this, he was gravely injured in battle," Mikey said slowly. "We can't fix him without outside help."

"Was it his arm?" Dr. Modha inquired, assuming that was why he had built the prosthetic.

"No," Michelangelo answered. "It was his knee. We took a scan when he was first injured. The video is saved on this flash drive. We'd like you to watch it, and see if you can think of some way to fix it. If you can, we'll pay you back by giving you all the designs for the arm, as well as the demonstration model."

Dr. Modha took the flash drive. "I'll watch it," she said. "How do I get back in touch with you?"

"Donatello's e-mail address is on there too," Michelangelo said. On his cue, the turtles disappeared back into the shadows. "You can take your time making your decision. We aren't going anywhere," his voice echoed through the deserted garage.

It took a few weeks for Donatello to receive an email. He gulped before he read it, deciding to do so on his own before speaking to his family.

"Dr. Modha wants me to come into the hospital for further testing," Donatello explained over dinner that night.

"But, she already has the scans," Michelangelo pointed out. "What other tests could she need?"

"Those scans are almost six months old," Don replied. "And, they were made with a low-resolution machine. She wants an up-to-date MRI. She also wants to run one on my other knee, so that she can see what a healthy mutant turtle leg looks like."

"So, what do you want to do?" Leo asked. Don hadn't left the Lair since he'd gotten hurt. At this point, he was essentially a shut-in.

"I'm scared, Leo," Don admitted. "What if this is some sort of trap?"

"She's not that type," Leo soothed. "She's got a personal stake in this too, Don."

"What's personal about money?" Donatello somewhat grumpily replied.

"There's a reason that we chose her," Raphael answered. "Her son is missing an arm."

Don looked back and forth between his brothers. "We've seen him visiting her," Michelangelo elaborated. "And, we found a news article about how she adopted him from an Indian orphanage. Apparently, he lost it to some sort of infection back when he was a toddler. She's a good person, Don. She only wants to help people."

"A lot like you," Leo added.

Don managed a reluctant shrug. "Well, if you trust her, I guess that I can too. She suggested that we set up a time to meet her at the hospital. It would have to be sometime in the middle of the night when it's less crowded. It'll be easier for her to sneak us in and out of the MRI machine that way."

The turtles made plans to do just that, a week later. It was strange for Don to be back on the surface. His brothers had tried to encourage him to come out these past long months. But, it hurt him too much to move for long distances, and he also feared not being able to run away if something went wrong.

This made it even more unsettling to approach the MRI machine. Don was trembling, and his brothers weren't sure if it was his pain flaring up from the van ride and the walk through the hospital hallways, or if he was simply feeling frightened and helpless.

It was a good thing that Dr. Modha had a well-honed bedside manner. She leaned over where he was lying in front of the machine. "Donatello, the scans won't be accurate if you're shaking. Do you need something for the pain, or to calm you down?"

Even Don wasn't sure what his issue was. He'd read that many people panicked during MRI testing, but Don held no fear of machines. He reasoned that he was afraid of being trapped in there if someone were to walk into the room. How could he defend himself, being disabled and stuck inside a machine?

"Your brothers will be right outside. They can even talk to you if you want," the doctor comforted.

"Tell me about your son," Don requested, hoping that a distraction would help him to feel better.

Dr. Modha was a bit taken aback, but she began speaking anyway. "Well, his name is Ravi. He's a remarkable child. Very spirited. I have a busy schedule and never saw myself adopting. But, I had volunteered to do some charity work at an orphanage overseas, and he just stood out to me. I knew right away that he was meant to be my son. He had lived in that orphanage since he was a toddler. He was four when I met him, about two and a half years ago. I was so inspired by his positive, loving attitude, despite his desperate circumstances. I just knew that I needed him in my life. So, I became a mom on the spot. I haven't looked back. Since I brought him home, he's really blossomed. He's friendly and brave, and intensely curious about the world."

"My brothers tell me that he lost an arm," Don said hesitantly.

"True, but it doesn't define him. People stare, but rather than be offended, he treats them as new friends."

Don had stopped shaking by now. "Listen… I want you to have my prototype. Even if you can't help me, I want you to have it."

Dr. Modha nodded. "Okay. But, I'll help you regardless. We're partners now."

Don smiled at that and realized that he was ready to submit to the tests. He relaxed his body, and into the tube, he went.

It was good practice for all that was to come in the next month. Dr. Modha couldn't do the surgery herself. She needed to consult with specialists, and bring in a surgical nurse and an anesthesiologist. People needed to cover the paperwork trail and ensure that there would be no record of the surgery, or any unwanted visitors while Don was in the hospital. The turtles approved each decision and thoroughly checked out each new person before agreeing to add them to the team. Fortunately, a lot of people owed them favors.

When the day of Don's surgery finally arrived, he had to say goodbye to his father and brothers prior to being wheeled into the operating room. It was scary for all of them, knowing that Don would be unconscious and extremely vulnerable, in an area where they wouldn't be able to protect him. Surgery is scary for anyone, but Don was a unique case. He didn't know how the drugs would affect him. He was afraid that he may not wake up. He was also afraid that he couldn't trust all these new strangers.

An orderly arrived to take Don away, and he found this new person's presence unsettling. "I… I'm not sure that I should go through with this after all," Don said in fear. "What if… what if this is some sort of trap?"

"It's not a trap, Don," Leo warmly replied. "You know how careful we've been. This is just last-minute jitters."

"Okay, but what if something goes wrong?" Don continued to fuss.

"It will be okay," Splinter comforted. "It will. You will wake up at home, in your own bed." That was the plan they had made, as convalescing in the hospital would drastically increase the odds of the turtles being discovered by someone outside the little team that they had built.

Feeling like an intruder, the orderly stepped forward. "Dr. Modha is the best. The whole team worked really hard on this plan. And, on a personal note, everyone involved owes your family a huge debt of gratitude. We're not about to betray you."

Don pulled himself together, partially due to a fear of appearing weak in front of this stranger. "What did my brothers do for you?" he asked shakily.

The security guard smiled. "Ah, the red one-"

"Raphael," Raph grunted.

"Raphael. He was persistent. Showed up here all the time. It was kind of unsettling if I'm being honest."

"Hey!" Raphael snapped.

The orderly laughed. "Well, it was! I've been dating a Paramedic, and sometimes we'd go out to the ambulance bay for a bit of privacy, and we'd catch a glimpse of him from a nearby roof, watching over everyone. It did put a damper on things."

"I never watched anything that should have been private!" an offended Raphael pouted.

The orderly didn't directly reply. "Well, I found it unsettling, until my girlfriend pulled up with some gangbanger under her care, and as soon as the ambulance doors opened, someone opened fire from the street."

Donatello gasped.

"She would've been caught in the crossfire, if not for your brother. The gunfire was coming from a car, and Raphael jumped down from a roof and landed right on top of it! He reached inside and grabbed the driver. The car went out of control and crashed into a light post. I've never seen anyone do anything so selfless."

"Pretty good, Raph," Don praised.

"Aw, it was nothing," Raphael dismissed.

"We all have stories like that. Until today, I never had a chance to thank Raphael," the orderly continued. "From the sounds of things, a lot of us New Yorkers owe us your thanks but have never had a chance to give it to you. So, if this is our chance to pay you back, then we're all going to make darn sure not to mess it up."

"See that you don't," Raphael half-threatened. The atmosphere had gotten too sappy for his liking.

"Okay," Don said thickly. "Okay. I'm ready now." He smiled at his family. "Bye Dad... guys."

They all took the chance to give Don a final hug. "We will see you before you know it," Splinter promised.

When Donatello regained consciousness, he was, indeed, warm in his own bed and surrounded by family.

Leonardo was the first to notice that his brother was awake. "Hi, Donnie. How are you feeling?" he asked.

"Fine," Don answered groggily. "How did everything go?"

"Very well, my son," Splinter replied. "The doctor said that you will be up and walking around in no time."

"Really?" Don questioned.

"Really," Leonardo affirmed. "Everything went perfectly. You may never get back to 100%, but you'll be head and shoulders better than you were before."

"You need to rest tonight, but we can try to get you up and about tomorrow," Raphael added. "She said that you should try taking a few steps with a walker."

"Really?" Don said again.

Michelangelo chuckled. "Why do you sound so surprised?"

"I guess that I was scared to let myself believe that it would really work," Donatello admitted. "It just seemed too good to be true, and there was so much that could have gone wrong."

"Well everything is just fine," Leonardo replied. "So you can rest easy tonight, knowing that you're finally on the mend."

"I suppose that you guys can finally rest easy too," Don said softly. "You sacrificed a lot of nights to pull this off for me."

"We did it for ourselves too," Raphael answered, his voice choked with a sentiment that ran deep within him, but that he rarely voiced. "We need you by our sides again. Like really by our sides. Not just because of all the things you do for us, but also because…. We just love you, Donnie. And loving someone means coming through for them when they need you most."

"Doing whatever it takes for them," Michelangelo added.

"I think you proved what you were willing to do for us, time and time again," Leo finished for all of them. "We were just returning the favor."

"Thanks," Don replied. He leaned forward in the bed and opened his arms wide. His father and three brothers gave him a firm but careful hug.

Michelangelo noticed that Donatello hadn't winced at all when he moved, and he couldn't resist the urge to try something out. "Hey Donnie," Mikey whispered.

"What?"

"What do you call a dog with no legs?"

"Huh?" Donatello grunted.

"What do you call a dog with no legs?" Michelangelo repeated.

"Mikey," Raphael muttered in warning.

"It doesn't matter what you call him. He's not going to come anyway," Michelangelo finished.

Donatello was confused for a moment, then couldn't help but let out a belly laugh. "What the heck, Mikey? That was terrible."

"But you laughed," Michelangelo replied.

"Only out of pity," Don quipped.

"Still, you laughed, and it didn't seem to hurt you," a self-satisfied Michelangelo observed. "You didn't even reach for your knee."

"I guess it didn't hurt," Donatello realized. "Awww. You guys fixed me." He opened his arms for another hug. Even if he never did make it back to 100%, he knew that he'd never lost those things that mattered most.

Funny story. I totally forgot about Don's knee injury in Homecoming. Apparently, I'm a repetitive author. I was going to rewrite this chapter, but I figured 'why bother.' At least you know what to expect from me! Anyway, thanks for reading!