(Author's Note:
First off, this takes place in the 2003 cartoon universe, because that is how I imagined everything in my head at six in the morning. Second, this isn't connected to CFR Crossfire, although it could be, because things are pretty damn vague. We could place it shortly before the events of that story, before Michelangelo becomes psionic, while they're still older and not having quite as many adventures, when they're nearly twenty and settling softer. Yes. Let's do that. My first 2003 TMNT fanfic that is separate from my other TMNT fanfics. Also, I officially headcanon Mikey as Donnie's assistant, because Donatello has got to be very tired.)

Laugh Til It Hurts

He was tired. He glanced at the clock. It had only been a few hours, really, maybe five hours? It hadn't been that long since the incident even happened, but it felt like so much longer now that there were no more millionths of a second feeling like forever.

Oh, he was tired. The adrenaline leaving should have been enough. His mind wasn't built for that, it just kept going. Heh. They were the same, really, he just kept forgetting because his brother was louder on the outside than he was on the inside.

He ran his hands over the bandaged arm again, feeling the pulse thrum steadily under his thumb, just because he could feel it and that felt good, seeing as just over five hours ago, he was feeling it strain and stutter and flutter and he didn't want to think about it.

He turned in the wheeled chair to adjust one of the hanging lamps, and heard a faint, groggy, "Hey, what's going on?" from the bed.

Donatello whipped around so fast the lamp swung. "Mikey, don't move your hand, I gotta check for nerve damage!" and he'd said it so fast he didn't realize. He blinked. "Oh, you're awake! Oh, good."

Mikey was watching him with lidded, foggy eyes, a little dilated, but they were the same blue, the same brightness. The bruising on his right temple and cheekbone stood out like purple shadows. He lay very still against the raised hospital bed they'd gotten years ago from a medical facility, and he was breathing very carefully. "Hey, Donnie. Is April okay? How long've I been here?"

"April's fine, we're all fine." Don gently lifted Mikey's left hand like it were porcelain, and ran the tips of his fingers across the palm. "Can you feel that?"

Mikey grunted. "S'tickly. Kinda burns."

Don nodded and moved his brother's fingers, one by one. "Feel that? Any numbness?"

"Still kinda burny."

"Burny is better than numb."

"Yep. You taught me that. Taught me lots of stuff."

Donnie bit his lip and moved down to the wrist itself, the gauze hiding the hasty stitches hiding the jagged flesh hiding the pierced artery, and maintained eye contact.

Mikey just blinked slowly like a cat. "It fucking hurts, Donatello."

He huffed. "Just checking. You know."

"I know."

"You remember what happened, Mike? You've got a concussion too, so go slow."

Mikey shifted, closed his eyes for a minute, his fingers relaxing and falling back against Don's hand. "Mmm. Big ninja battle. We took some heavy hits. I 'member, April had that old artifact they wanted, I was helpin' her get to a safe spot…Casey was right behind us…"

"Yeah…"

Mikey blinked and locked eyes with him, the brightness increasing like a light through a door. "One of the ninjas came at us to get the artifact. I fought him. He…he hit me in the head and…um." He swallowed thickly.

"Go slowly, remember." Donnie's thumb massaged slowly.

"Yeah. I saw the kunai coming. My arm was already up. Y'know the moments where time slows like that?"

Donnie did know. Donnie had those moments, had one just over five hours ago, at the sound of April screaming his name and the sight of her already splattered in bright blood that wasn't hers.

"Yeah, that. That's all," Mikey said. "I'm guessing I got hit with the kunai."

"You did."

"I'm guessing it was bad."

"It was."

"Who got the ninja?"

"Casey clocked him while you were going down," Donnie said, swallowing. He didn't want to think about that.

"So, how much blood did I lose?" It was a conversational tone from an eternal optimist.

Don huffed again. "Little over a liter and a half? You know. Enough to nearly die but not quite enough."

"Oh!" And Mikey lifted his right arm and pressed the back of his hand to his forehead, taking on an affronted posh accent. "Nearly, but not quite enough. Heavens."

And Donnie struggled to keep the line of his mouth straight, because he couldn't crack on this one, he couldn't, not now, but…

"Well. You. Um. April said your pulse was gone and I doubled-checked after Casey and I finished the suturing..." He coughed. Yup, his voice was cracking. Damn.

Wide blue eyes now and the brightness was enough to shine. "Whoa. I…my heart stopped?"

Don shrugged, tried to, managed a hunched sort of shudder. "I…no, but you came close. She couldn't feel it but I could. It was so soft, Mikey, like a flutter. It was so much…less than you. I could feel and hear it because our senses are better than humans, and I know our bodies, and it was so weak that of course April couldn't find it."

"Donnie…" the raspiness betrayed his exhaustion, but Mikey was sitting up, struggling, and grabbed Donnie's arm with his good hand.

"Donnie."

"You know, none of us have ever had an arterial bleed that badly, not like that, and I kept thinking, in those millionths of a second where time slowed down, I kept thinking, what if it doesn't work? What if Mikey's body and brain isn't actually as tough as we thought, what if I'm too slow, what it was already too late…"

"Donnie, hey, no…stop…"

"And I knew that just an arterial bleed couldn't cause complications and just a concussion couldn't cause complications, but you mix the two, and however many other little hits you took, and that, combined with our shitty luck, that would be enough to cause complications, and there would be hypovolemic shock, and with concussions and unconsciousness you are never certain about recovery time, with blood loss it's easy but with head injuries it could be hours, or weeks, and then you have to consider brain damage, especially since the bleed would cause oxygen loss anyway and you would worry that maybe there wouldn't even be a full recovery…"

"Donnie…" and Mikey's voice was raw and so small.

"And I'm so fucking grateful it was only a few hours, Mikey, it could have been longer, it could have been months, and I still need to give you some neurological tests to see if there was any damage, and you'll be dizzy and disoriented anyway, and you'll have to tell me every little symptom, okay, even if you mess up words, because that could indicate cognitive damage…"

He was shaking now, desperately holding that bandaged hand in both his own as if it were a baby bird, running his thumbs over Mikey's palm and then his wrist, pressing, pressing down to feel the steady pulse, because just over five hours ago—

"Donnie, stop, I'm sorry!"

His head jerked up. "Wh-what?"

Mikey was staring at him pleadingly from the pillows, right into his eyes, and Mikey was wide-eyed as he could be, puppy dog gaze, mouth open and quivering, eyes wet and far far too bright. The bruises on his head like empty eyes, like dead stars, turning yellow at the edges.

"I'm sorry. I'm sorry I got hit in the artery with a knife, I'm sorry I let myself get thwacked in the head, I should've blocked better, I should have known better because I'm your assistant, and I'm sorry I almost died on you, I'm sorry…"

And Donnie stared and stared, and felt his eyes go really wide. And the tangled murky sensation bubbling up from his insides burst and became a sharp laugh. "Yo-you're sorry."

Mikey was panting. "I'm sorry, Don."

"You're sorry. You're apologizing. To me."

"Y-yeah?"

"You're apologizing to me for almost bleeding to death. You're sorry."

And he couldn't. He laughed again. Haha, nope. He giggled. "Oh my…ohh, Mikey." Another bark of laughter. "Oh, Mikey, you beautiful dope."

"Whu?" And Mikey's utter confusion became slow realization. And he started giggling. "Holy shit. Dude. What?"

Don giggled again. "You fucking idiot, you don't apologize for almost fucking dying!"

"The fuck! I know, dude!" And Mikey laughed louder, harder, rough as hell because he was still fatigued, voice grainy and rasping because of the damn head wound and the time unconscious. "What? Like, wow, what?"

And that was all they could do, laugh and snort and giggle at each other helplessly, because what the hell else were they going to do, and he had promised the universe that if only Mikey would smile he would give anything, he just needed to hear his brother laugh then everything would be all right, because Mikey was the reason everything was always all right, as long as Mikey could laugh things were all right, and dear science and stars, Mikey couldn't die, not without smiling one more time, and his laugh—

Mikey was laughing, and tears were streaming down his face, his head thrown forward as he grasped Donnie at the back of the neck and yanked him close until their foreheads bumped hard, and they were crying and giggling, their tears and laughs blending, and "fucking idiots, we are such fucking dorks" and Donnie snorted and his ribs were aching and he couldn't stop—

"What the hell? Mikey! Hey, Mikey! Uh…Donnie? Yooouu guys okay?"

Raphael's pure plain bafflement set them off again, and they yowled until they were heaving. Donnie was gulping for air.

Mikey, the consummate professional, drew in a long slow breath that Donnie could feel through his own torso. "Hey, Raphie. Hey, Leo. It's cool. It's all good. I'm an idiot and Don is a dork."

"This is new?" Leo's voice came, and Donnie chomped on his lower lip, sitting up. Mikey was looking at their very puzzled brothers, gently massaging his left arm and smiling prettily, fucking damn it, how did Mikey make it looks so effortless, Don was wiping his face messily, and he smiled wetly, his lower lip still trembling.

"Really good to see you awake, Mikey," Leo said, in that soft special voice he used just for the youngest brother, the one that told everyone how desperately wildly worried and scared he had been but had been holding everything together for the family.

And this was why Donnie had started training Mikey in medical care specifically a couple months ago, to take some of his weight, to help him go back to being the science-minded philosophical engineer with a passion for physics who had to learn things like internal medicine and minor surgery as a child because he was the only one who really could. Because now he had time and opportunity, and Mikey had the passion to learn, he always had, he just needed things that really excited him, and Don had never seen him light up quite like when Donnie had given him the first textbook. Mikey had asked for psychology and neurology next, and Donnie had discovered that his little brother could read as well as he could if it was something he loved the way he loved comic books, and he loved psychology and biology and he had always been so good at reading his brothers' emotions and bodies and auras, and now he knew so many things that could help their minds, and Leo especially had benefited, he wasn't so tense, it was like Mikey had become an instant family therapist, and Leo had changed in new ways. Not to mention Raph, whose regular rages had almost completely stopped just because he and Mikey went to Raph's room and talked for hours every couple of weeks, and Raphael would be smiling all day after. And Mikey had that aura thing that Splinter talked about, that spiritual energy manipulation, almost as good as Splinter, he could change their auras, touch their energies, he could make them smile without them realizing, and sure, it was a little scary to imagine being on Mikey's bad side of literal emotion manipulation, but Mikey loved them so much, more than stars in the universe.

"Yeah," Mikey grinned, his easy sweet Chesire cat grin. "Bet it was really freaky for a minute or three there."

Donnie looked at Raph and pressed his lips together, another minute or three and everything would have ended, and he automatically checked his bulky older brother's pallor, still slightly off from the transfusion but no sweating or shakiness, good, good, April's hands had been good at slowing the flow of blood, kept it from gushing all over her, and then Casey had clamped his own meaty hands over the torn flesh as Donnie had gone emotionless and cold and started the first of eight stitches, Casey pressing and using his bandanna to mop away enough blood so Donnie could keep stitching, eight stitches, and then April had spoken up in a tiny tremulous voice that she wasn't finding a pulse anymore…

Don's eagle eyes swept from brother to brother in a millionth of a second, seeing Leo's entire body visibly relax, his eyes lose that tightness at the edges, his legs already moving, his hand already reaching out to cup the back of Mikey's head and rub it the way they all did when he was upset, that little comfort that did so much because it meant he smiled, like he was smiling now, that content childlike turning up of his mouth, eyes closing and squeezing at the corners, the visual sigh that loudly proclaimed that everything was all right now, they could go back to their lives, everything was going to be fine, and then his bright blue eyes opened wide again, still childlike as his upturned mouth opened and then he raised his right hand and pointed at Don.

"I apologized to Don for almost dying."

Raph's head tilted like a large, confused bird's. "Why the fuck would you do a stupid thing like that?"

"That's what I said!" And Mikey giggled again, high-pitched, and Donnie burst into a fit of his own, again, and they glanced at each other, and the laughter was rolling off them in waves, Donnie felt it, like a wave of sunshine followed by a soft breeze, because that's what Mikey is, and out of the corner of his eye he saw Leonardo smile wider, his shoulders shaking, and suddenly Leo was laughing softly, chuckling in that way he had, my brothers, oh my silly brothers, and Raphael was just staring at them, staring, and Donnie laughed harder and Mikey laughed harder and Leo laughed harder.

Because it was so funny, wasn't it, whoops, almost died there, that would've sucked, us being the only creatures like us on the whole fucking planet and all, oh dearie me and it would have been in that prissy bratty voice Michelangelo liked to use when things were getting really weird and needed sarcasm, he would have said it like an affront, gotcha again, universe, can't keep us mutant turtle ninjas down, fucking tragic, what you get is what you see, with his little hip wiggle like a middle finger to the cosmic forces.

And Raph finally snorted, loudly, and Mikey yelled "PAH!" and pointed at him, and that made Raph laugh in a way that sounded like bellows, like the rumble of a storm rolling in right on top of you, his wide shoulders heaving as he bent forward, slapping his hands against his knees, and he was looking up at Mikey with golden eyes shining, that endless way he looked at him, you make me feel safe, you contain me, you relax me, give me your smile and I know everything's okay. And Donnie felt his tears start again, because oh why was it so fucking funny!

"Uhhh…"

That was Casey.

Still snickering, they all looked up at once, to the infirmary's doorway, where April and Casey were standing, with Splinter slightly behind leaning contentedly on his stick, eyes sparkling.

Casey frowned, scratching the back of his neck. April was holding his hand, looking a little shell-shocked, well, still, and Donnie noticed that her eyes had a foggy faraway look, well that would happen to anyone who was holding one of their best friends who was bleeding out all over them, wouldn't it, and in that millionth of a second Donnie had time to remember how he had seen her face completely devoid of color except for a tiny spray of red droplets against her cheeks, how her mouth had been forming words like Mikey's hurt and wrist, artery, and it was all he needed to know before he even saw the blood and Mikey's body cradled against her like a child, her hands clamped around his left arm covered in blood and it was bright red, not dark, no, it was the bright red that could almost be orange, like that hotter part of fire, like his mask in dim lighting, and it was all over her hands and Casey was dropping to his knees and yanking the bandanna from his neck as Donnie slid on his knees (and the blood was painted onto his knee pads but that could have been water, it could have been a puddle) and Donnie told her to keep checking his pulse and Casey took her place, his hands, the bandanna, soaking in that bright orange-red.

Donnie sniffled, his cheeks aching so fucking hard, and he gave them what he hoped was a reassuring smile, because he didn't even know anymore. April's eyes went to Mikey and softened in extraordinary relief, immeasurable gladness, a deep wide shadow of guilt like a passing eclipse. "Mikey," she breathed, "you're okay, you're awake, oh my god."

And Mikey tilted his head just slightly. "Yeah. Hey, you okay, April?"

April slapped a hand to her sternum, jaw dropping. "Y-you're asking if I'm okay?"

And that was it. Donatello fell to the floor, smack, his shell making a satisfying thud, laughter rolling through him like thunder as he threw back his head and howled and whooped and he heard his brothers scream and roar in absolute mirth, and his heels banged against the floor as he fought for breath. Above him, he heard Michelangelo take another round of slow, deep, calming breaths, silent for a full second, how the hell does he do that so well, how can he just control laughter like that, like a god of laughter? And he opened his eyes to see Mikey leaning over the rail of the infirmary bed, Leo supporting him.

"You fucking amateur, get off the floor," Mikey grinned at him tiredly, and Donnie immersed himself in another fit of cackling, rocking on his shell, before Casey helped him back on his feet, and Donnie shoved his fist in his mouth and it wasn't quite working. How the hell did Mikey know how to laugh and how to stop laughing, it was like a magic trick. In that millionth of a second, Don looked at his little brother, eyes twinkling merrily in a face finally coming back to its full color, smiling gently and benevolently, holding all the secrets of happiness in the universe.

"I love you, you little asshole," he said joyfully.

"Love you back, you fucking dweeb." And Mikey turned the sun back on with the sparkle in his eyes, and Donnie managed one last laugh, finally relieved, finally able to relax, because everything was all right.