A/N: This is going to be another long, angst and fluff, and horrifying drama story. I can just feel it. Not to spoil too much for you guys, but there's going to be talk of involuntary medical procedures, child abuse, Howard's bad parenting ratcheted up to 11. If you're squeamish about that kind of thing, you might want to get out now. But for the rest of you, enjoy the angst!

Disclaimer: This is another avengerkink fill so the general plot is not mine. I just filled in the specifics.

It was so wonderful to finally have Bucky back. All of him.

For so long, he had seemed like nothing more than an empty shell, like a robot wearing Bucky's face. But gradually, Bucky's memories had started returning and with them, his personality.

Now Steve genuinely felt like he belonged here in the future. The Avengers weren't the Howling Commandos, but they were really starting to function as a team, to work together as well as the Commandos had. And crashing in the den after a successful mission brought back warm memories of sitting around the campfire with his men, swapping stories.

The team had welcomed Bucky into their midst as if he had always been one of them. Natasha and Clint regularly sparred with him in the gym. Bruce shared some of his favorite recipes with him. And in between Thor's countless retelling of his glorious battles in Asgard, Bucky was beginning to offer tales of their exploits during the war.

It really was heartwarming to see the entire team taking the time to come together like a family.

Except for Tony.

"-and so there we were, fifteen Hydra grunts on our tail," Bucky said, flashing Steve a grin. "But we had this bazooka Howard Stark had modified for us out of-"

Tony snorted derisively. "Didn't happen. My dad never built guns, just bombs. "

"Oh," Bucky said. His smile wavered and doubt started to creep into his eyes. "I could have sworn it was a gun." His brow furrowed and he looked into the distance, seemingly deep in thought. "Was it really a bomb?" he murmured.

"It was a gun," Steve said firmly. "I watched him make it."

He shot Tony a glare. Bucky didn't need anyone undermining his recovery.

"Of course you did." Tony leaned back in his seat and took another gulp of his whiskey. "Bet you watched him make every single weapon he ever gave you. Because everything he did was just so fascinating and amazing. Nothing like the boring stuff we have here in the future, right?"

And just like that, the peaceful atmosphere was shattered. Instead of laughing with each other, the rest of the team had gone silent. Steve could feel the tension in the air and see the apprehension in Bruce's face.

"We've all had a long day," Natasha said carefully. "Maybe we should just call it a night."

"Hell no," Tony said. "I want to hear the rest of this story. Don't we all? Howard Stark builds a fucking gun, and then what? A bigger gun, maybe? Whoa, what a plot twist. Gee, Barnes, that sure was an exciting story. Maybe next week we can hear Steve's side of it. And I'm sure he can tell us all about that bazooka down to the last detail. Because he watched it being made, remember? Boy, after all that time kissing my dad's ass, it's amazing he had any time for that girl of his."

Steve rose to his feet, controlling his anger with great difficulty. "That's enough," he said. "You're calling it a night. Right now."

Tony scoffed. "You gonna make me?"

"Yes," Steve said. He hauled Tony to his feet. "Bed. March."

Tony rolled his eyes. "I'm not a child."

"Well, you're acting like one," Steve said. He gave Tony a shove in the direction of the elevator. "Get going."

"I'm calling it an early night, too," Bruce said. He slipped out of the room and headed for the stairs.

Natasha was right behind him.

"Fucking cowards," Tony called after them.

Steve grabbed Tony by the shoulders and shoved him up against the wall. "You need to stop," he said. "We're not your enemies."

"You're my dad's friend. Which is pretty much the same thing. You heard about Obadiah Stane, right? Dad's old business partner? Tried to fucking kill me."

"Nobody in this tower is going to kill you," Steve said. "And you know that."

"Right. We're all too polite here for murder. We'd rather just beat the hell out of each other and call it a night." He tipped his head to one side and patted his cheek. "Come on, big guy. Giving you a free shot."

"You're drunk," Steve said. "So I'm going to pretend you didn't mean a single word you said tonight. But next time you're an asshole to Bucky, yes, I will punch you." He released Tony's shoulders. "Sleep it off. I'll see you in the morning."

"Yes, sir," Tony said with a sarcastic salute. He stumbled backwards into the elevator and the doors closed in on him.

Steve didn't see Tony the next morning at breakfast. Not that he had really expected to. After how drunk Tony had been, he probably wasn't even going to get out of bed until noon. And if he remembered even half of the things he had said, he'd probably avoid everyone until the next Avengers call.

Natasha slid into the seat at the table across from Steve. "I haven't seen him that drunk in awhile," she said. "It's not a good sign."

Steve shook his head. "I don't know what's gotten into him lately."

He and Tony had never been the best of friends, but they had gotten along pretty well in the years after the Battle of New York. Now it was like all that time was erased and they were back on the helicarrier again arguing with each other.

"It's probably my fault," Bucky said. "You two got on so much better before I showed up."

"Not true," Steve said.

For the first few months Bucky was with them, Tony hadn't been this hostile. He had made one weirdly insensitive comment about Bucky's long hair, insisting that he needed to have it cut so he wouldn't look like a girl. But he had also eagerly fixed Bucky's arm, and given him a whole slew of nicknames. And if Steve knew anything about Tony, all those silly nicknames were his way of showing affection.

It was only in the past few weeks that Tony had really started acting up, getting combative during missions and spending the evenings either avoiding the team gathering in the den or just dampening the mood with his attitude. Yesterday had been by far the worst, but Steve was afraid Tony's behavior was just going to keep escalating. And he had no idea what was even setting him off.

"If I may," Jarvis said. "This year will be the twenty-fifth anniversary of his parents' death. Sir is expected to make a statement in remembrance of his father sometime next week."

"Oh shit," Bucky said.

Steve squeezed his eyes shut. Of course this would be an emotional time for Tony. And instead of turning to the team for help, he was pushing them all away.

"Thanks, Jarvis," he said. "Let me know when he gets up so we can have a little heart to heart."

"Sir is already awake and downstairs in the lab," Jarvis said. "But he may be too inebriated to fully appreciate your message."

"Well, I have to try anyway," Steve said. Because if Tony was starting every morning drunk to cope with the pain, it was long past time for an intervention.

"Very well, Captain," Jarvis said. "I have left the doors unlocked."

Good. Steve pushed aside his plate of eggs and headed downstairs.

Tony was sprawled on the floor next to one of his worktables, half a bottle of scotch clutched in his hands. He looked up at Steve's entrance, his eyes glassy and unfocused. "Oh, hey. Guess you're here for the lecture," he mumbled.

"No lecture," Steve said. "I come as a friend." He crouched down beside Tony and gently eased the bottle of scotch out of his hands. "A friend who's concerned about your health."

"Don't worry about it. My liver's seen a lot worse," Tony said. He made grabby hands for the bottle.

"Your mental health," Steve said, maneuvering the bottle further out of reach. "Jarvis told me about the statement you're making about Howard."

"Oh, yeah. That." Tony gestured up at the bench. "Got this wonderful canned speech right here. All of Dad's greatest achievements and not a single mention of what a goddamn asshole he was to me growing up. I bet you still think he was the awesomest man alive because of all the cool shit he made you. But let me tell you, he was the world's shittiest father. Always on about you. And I could never compare to that, you know. How the hell could I? You have the supersoldier serum and I was born, well, I was born a failure."

"You're not a failure," Steve said. "I'm sorry if Howard ever said that to you. He shouldn't have. And he should have never made you feel like you had to live up to my accomplishments. Captain America was supposed to be a role model for doing the right thing, not some impossible standard you could never live up to." He shook his head. "I wish Howard had paid attention to what we were really fighting for."

Tony snorted derisively. "Yeah, tell that to everyone who thought Dad was some big saint just for being in the war. How dare I have anything negative to say about him because he's a fucking war hero and that means he's absolutely perfect and can do no wrong. Fuck the war. Maybe Dad should have died in it."

"You don't mean that," Steve said. "You would have never been born."

Tony shrugged. "Maybe it would have been for the best. I'm sure that's how he felt sometimes."

"Come on," Steve said. "He's been dead for twenty-five years. You need to stop letting him dictate your life."

"I can't," Tony hissed. "He made sure of that. Made sure I was the perfect son that he always wanted."

"Tony, you're-"

"There is an incoming alert from Director Fury," Jarvis said.

"Fuck." Tony heaved himself to his feet. "Jarvis, gimme a suit."

"That would be inadvisable, Sir. You are currently-"

"Oh, don't give me that shit. I've done half a dozen drunken joyrides by now and I've survived just fine."

Steve was horrified. "Tony, you shouldn't play around with this kind of technology. You could get yourself killed. Especially in the middle of a battle."

"I appreciate your concern," Tony drawled. "But if I die, I die. And it won't make a fucking difference." He gestured impatiently with one hand. "Jarvis, suit. Now."

"Tony, you're not-"

"Don't you fucking dare tell me I'm not good enough to help save the world," Tony snarled as the suit snapped into place around him. "Even a failure like me can do his part."

Steve sighed as Tony dropped down through the secret door into the underground garage. In a matter of seconds, Tony would be out of the Tower, flying into battle. And there was nothing he could do to stop him.

"Suit up, team," he said into the comm. "Take-off's in five."

Not that anyone needed the whole five minutes to get ready. Everyone was pretty much ready in two minutes flat. Even Steve, who needed to run back upstairs to grab his gear was on the jet before the five minutes were up.

And Tony was still giving them grief about it.

"Took you long enough," Tony grumbled as the Quinjet swooped down over Battery Park. "Would it kill you all to leave your shit on the jet so it's ready to go?"

"And would it kill you to wait for the rest of us?" Steve shot back.

From what he could see, Tony wasn't in any real danger. No fire and explosions and no villain of the day causing trouble. He studied the mission briefing on his tablet. According to Fury, some mysterious structure had appeared in the middle of the night and it was suspected to be another magical artifact. So, they were supposed to be on scene in case anything popped out.

"Set her down, Clint," he said. "Let's check it out."

The object turned out to be a huge metal circle sitting on a raised platform. It didn't exactly look like a magical artifact. It was entirely man-made, judging by the wires Steve saw connected to the circle. But then again, there was nothing that said it wasn't powered by magic. He had seen enough weaponized magic in his day.

Bruce pulled out a Geiger meter and walked slowly around the structure checking for radiation before he considered it safe for the team to approach.

"What is this thing?" Steve asked. He cautiously ran a hand over the curved metal frame. So far, the thing was staying entirely dormant.

"Fuck if I know," Tony said as he came in for a landing. "Jarvis is running a material analysis right now."

"I've seen this type of thing before," Clint said. "Or something like it anyway. It looks just like one of those portals in Big Hero 6."

"That's a kid's movie," Tony scoffed.

"Sure, the kids love it, but it's so much more than just a kid's movie. We should watch it next movie night."

"Yeah, count me out," Tony said. "I'm only into adult entertainment."

Steve rolled his eyes. "What did the portal in Big Hero 6 do?"

Clint shrugged. "Basically teleported things from one place to another through a different dimension or something. But you'd want a second one for the things to come out of."

"Unless you don't want them coming back," said a voice behind them.

Everyone whirled around, weapons drawn.

The man that walked up was thin, balding, and almost blind judging by how thick his glasses were. But Steve knew better than to judge bases on appearances.

"Are you the one behind this thing?" Clint demanded.

The man smiled. "I am. And it's so nice of you all to come and investigate my little creation." His eyes gleamed. "I knew this would be the perfect lure. The perfect scheme for Hydra to finally finish the Avengers once and for all."

Bucky stiffened.

"Hydra will never win," Steve said determinedly. "We've destroyed enough of your bases by now. You should learn not to take us on."

"Oh, I admit that it has been very difficult to kill you. But if I send you back in time, I can let old age do the work for me." He tipped his head back and laughed. "Forty years should do the trick for most of you." He pressed a button on his belt and the portal began to hum, the air shimmering in the middle of the circle. "Enjoy, Avengers. I look forward to seeing you all as-aaaagh!"

Whatever he had been about to say was cut off when Bucky tackled him to the ground.

"Good," Tony said. "I was sick of hearing him talk."

Steve watched as Bucky wrestled the squirming Hydra agent into a chokehold."Since Bucky seems to have this guy covered, how about you figure out how to tear this thing apart so nobody else can try this scheme?"

"It's always up to me, isn't it?" Tony grumbled.

"I can lend a hand," Bruce offered.

"Good. The two of you work on that. Nat, can you call SHIELD and-"

"Tell them we inspected the area, caught the man responsible, and are neutralizing the threat?" she asked with a smile.

"Yes, good. All of that. Have them send somebody to pick this guy up."

He watched as the man's struggles became more and more feeble. When Bucky finally released him, he just flopped to the ground and didn't move. Steve wasn't concerned. The man was just out cold for a few minutes. They were way past the days when he had to tell Bucky to let go before he killed someone.

Steve frowned. The man wasn't moving any longer, but the flashing button on his belt certainly was. He looked up in alarm as the portal's hum got louder, the air inside the circle churning like waves.

"Turn if off, Buck," he ordered.

"I can't," Bucky said. He jabbed the button a few times without luck. "Thing only comes with an on switch."

Steve raised his voice to be heard over the rapidly intensifying humming noise and the sound of the air rushing past. "Bruce, Tony. You two have any ideas?"

"The portal's destabilizing," Bruce shouted back. "Looks like it's going to collapse in on itself."

"Okay, everyone clear the area," Steve commanded. He took a large step back and quickly scanned the area for civilians.

There was no telling what would happen once the portal collapsed. Hopefully it would just swallow itself up and fall apart. But he had seen so many movies about malfunctioning technology sucking in everything around it before exploding like a supernova. And there was no telling how big the blast radius would be if it really exploded.

Tony hovered a few feet overhead. "I could probably power it down before it explodes."

"No, too risky."

"You wanted the thing turned off, didn't you? Well, I'll turn it off. We'd all rather have a functional time portal than a pile of junk, right?"

"Speak for yourself," Clint said. "Would you really want to go forty years into the past?"

"Forty years ago. I would have been...I would have been five," Tony murmured so quietly that Steve doubted he meant anyone to hear him. But the comm picked up just about everything.

"Get out of there, Stark," Steve said as Tony drifted downwards, apparently still lost in thought.

Tony straightened into a take-off position, but continued drifting downwards. "Uh, big problem," he said. "The energy readings this thing gives off is fucking with my tech."

And then the portal's metal frame began rocking back and forth, what appeared to be lightning flickered in the air. Tony yelped as he abruptly dropped two feet through the air.

"No, this cannot be happening," Tony said. "Damnit, Jarvis, give me more power." His repulsors looked like they were firing at full power, but he was making no progress escaping from the portal's pull.

Steve watched in alarm as cracks started appearing in Tony's armor, little fissures that started by his feet and went all the way up to his thighs. "Tony, get out of there right now."

"I can't," Tony said. "I-oh shit." The repulsors on Tony's feet went out and he flew backwards into the portal, feet-first.

"Tony, no!" Steve shouted. He lunged forward and grabbed onto one of Tony's gauntlets.

"Shit, shit, shit," Tony said. "It's shredding my suit."

"We have a lot more to worry about than your suit right now," Steve snapped. Tony was up to his shoulders in the portal. And even with Steve trying his hardest to pull him back out, inch after inch of Tony's body was disappearing through the shimmering air.

"Steve, please," Tony gasped out. "It's going to suck you in, too."

"I don't care," Steve said. "I'm not letting go." He ducked as another piece of Tony's armor chipped away, revealing part of Tony's neck. And then the helmet cracked open.

He had a brief glimpse of Tony's terrified face before it disappeared behind the portal.

All that Steve could see of Tony now was his gauntlet. And not for much longer. Already he could see his own fingertips disappearing through the portal. But he kept holding on.

Tony's gauntlet was coming apart under the pressure, pieces sloughing off as easily as dead skin. Steve struggled to keep hold of him, clamping one hand around the genius' bare wrist. Impossibly, he found himself having to keep tightening his grip just to keep hold of him, as if Tony's wrist was shrinking smaller by the second. And little by little, Tony was slipping out of his grasp.

But then he felt Bucky's arms wrapping around his waist, anchoring him in place. He dug his heels into the ground and tugged backward with all his strength.

There was a sickening metal screech and then they all went flying backwards as the portal exploded. Steve hit his head against a rock and was knocked out for a moment. When he came to, Bucky was dazedly struggling to his feet, a little trickle of blood oozing from his forehead. But it could have been worse.

Steve sat up and surveyed the rest of the team. "Where's Tony?"

Clint shook his head grimly.

"No," Steve said. "That's not possible. I had him. I pulled him out before the thing exploded."

"Nope," Clint said. He pointed towards the playground. "You pulled her out instead."

Steve followed his gaze. At first he saw an empty playground. But then he spotted the dark-haired girl crouched behind a bench. His heart sank.

"Well, this is great," Bucky said. "We lost Tony somewhere in the seventies and we pulled this girl into the modern world. Way to go, Steve. Now the whole space-time continuum or whatever is going to be fucked."

"But I had him," Steve said. He looked down at his hands, remembering how small Tony's hand had felt in his. "It doesn't make any sense."

"Nothing makes sense these days," Bruce said. He picked at a piece of the machine's remains. "But I think I might be able to fix this and make everything right again. In the meantime, we have to figure out who this little girl is and when and where she came from so we can send her back. And she'll have to stay with us until I get this repaired. We don't want to mess up the timeline any more than we already have."

Steve nodded. "Okay, team. Let's do this." He headed towards the playground, most of the team following behind him.

The little girl shrieked and ran across the playground, diving under the slide. "Go away," she said. "I don't have any money."

"We don't want your money," Clint said. "We just want to talk."

"I don't know anything," she said. "Daddy's projects are secret. He doesn't even let me down in his lab."

"We don't care about that either," Bucky said.

"Back up," Natasha said. "Give the poor girl some room."

Clint huffed, but everyone took a few steps back.

Natasha knelt down beside the slide. "It's okay, sweetheart," she said. "We're not going to hurt you."

"Then why are you all dressed up like evil goons?"

Natasha's mouth twitched. "We're not evil goons," she said. "We're secret agents. We work for an organization called SHIELD."

The little girl nodded eagerly. "So does my daddy."

"Good," Natasha said. "Then you know we're the good guys." She held out a hand. "My name's Natasha. What's yours?"

"Tanya."

"Nice to meet you, Tanya. These are my friends," Natasha said, gesturing to the rest of the team. "We're all going to work together to make sure you get back to your family. This is Steve." She motioned for Steve to step forward. "He's-"

"Captain America," Tanya said, her eyes wide with awe. "You're amazing."

"Well, I try," Steve said with a smile.

Tanya crawled out from under the slide and took a tentative step forward. "I can't believe you're really here. Daddy said your plane went down in the ocean and nobody could find you."

"He's right," Steve said. "But eventually, people found me and rescued me. And now I'm here."

"I can't wait to tell Daddy," she said with a wide smile. "He'll be so happy to see you again."

"Your dad wouldn't happen to be Howard Stark, would he?"

Her eyes widened. "How did you know?"

Steve chuckled. "Just a lucky guess."

"Odd," Clint said. "Tony never mentioned having a sister."

Natasha shook her head. "It's not in his file."

"What file?" Tanya asked. "Do you have files on everybody like the FBI? Do you spy on people with binoculars and find out all their secrets?"

"Not exactly," Natasha said. "But we have gone on a few undercover missions to get intelligence. This is my partner, Clint. He goes by Hawkeye in the field."

"Because he's like the guy in M.A.S.H?"

"Uh, no," Clint said. "I'm an archer, not a doctor." He notched an arrow in his bow and casually aimed upwards. A pigeon plummeted to the ground at his feet.

"Whoa," Tanya said.

"And that's why the call me Hawkeye," Clint said as he stowed his bow. "Best shot in SHIELD."

Natasha rolled her eyes. "Don't mind his theatrics." She turned to Bruce. "This is Dr. Banner, our resident scientist. He's going to reconstruct the portal that brought you here and get you back home."

Tanya solemnly shook his hand. "You must not be very good if Daddy hasn't talked about you."

Steve sighed. There was that good old Stark sensitivity. It had to be genetic.

To his credit, Bruce just smiled faintly and said, "I hope you change your mind when I get this thing running again."

"And this is Thor. He's uh, he's a Norse god from the planet Asgard." Natasha frowned. "It's kind of a long story."

"Greetings, small one," Thor said. "I am very fond of your attire."

"Oh, this?" Tanya grabbed hold of the hem of her short pink dress. "This is just my play dress. Daddy doesn't like me wearing it around the house so I can only put it on when I'm playing in the yard."

"It is still a very beautiful garment," Thor said. "A most flattering shade."

"Ballerina pink," Tanya said. She spun in a circle, the dress fanning out around her. "I want to be a ballerina when I grow up."

"I am sure you will be a most excellent ballerina," Thor assured her.

Natasha cleared her throat."And this is Bucky," she said. "If you've heard of Captain America, you've heard of his best friend, right?"

Tanya frowned. "Daddy told me Bucky died." Her eyes traveled over Bucky's metal arm. "Is he a robotic replica?"

"Nope," Bucky said. He flexed his mechanical hand. "Just a cyborg."

"Wow. I don't know why Daddy always wants to talk about Captain America when you're so much cooler. No offense," she said with a quick glance at Steve.

Bucky chuckled. "I was just a normal guy back in the day. The arm came later."

Tanya tentatively reached out a hand. "Can I touch it?"

"Of course." Bucky squatted down and let Tanya run her hand all the way from his fingertips to the attachment at his shoulder.

She squealed with delight. "This is so cool." She moved back to Bucky's hand, turning it over so she could trace a finger over his palm. "I've never seen anything like this before."

Bucky twitched. "That tickles," he said.

Her eyes went wider. "You can feel things through the metal?" She made another more frenzied examination of Bucky's arm. "How does that even work? How is it connected to your nervous system? What is this even made of?"

"I don't know," Bucky said with a snort. "I didn't make it. You'd have to ask..." He faltered.

"We can show you the schematics in our lab," Bruce assured her.

Tanya smiled wide and bright. "I can actually come see your lab? Daddy's always afraid I'll break stuff so he never lets me watch. And it's so unfair. How am I ever going to be an engineer when I grow up if I don't get practice in a real lab?"

"I thought you wanted to be a ballerina," Clint said.

"I do. But I also want to be an engineer. Can't I be both?"

"Of course you can," Steve said. He was already growing fond of this sassy little girl. It was really too bad that Howard had decided to put the weight of all his expectations on Tony.

Thor lifted up his hammer. "Come with me, little one. We shall take to the skies."

"I don't think that's a good idea," Steve cautioned. "Too dangerous."

But Tanya had already scrabbled up onto Thor's shoulder. "Can I braid your hair when we get to your place?" she asked.

"I would be honored, little one."

She squealed and wrapped her arms around his neck. "You're my favorite."

"You can braid mine, too," Bucky offered.

"Awesome," she said. "First I'll check out the lab. Then I'll braid Thor's hair. And then yours." She flashed them all a smile. "Don't worry. I'll make you all really pretty."

Bucky laughed and shook his head as Thor took off into the skies, Tanya whooping with joy as she clung to his arm. "Bet you wish you had long hair now, don't you?"

"Nah, I'd look ridiculous," Steve said. He gave Bucky a side-eye. "Just like you will in a few hours."

Bucky shrugged as he vaulted up into the Quinjet's hold. "It'll be worth it."

It would, Steve agreed. Whatever it took to keep Tanya happy until she could be sent back to her time.