Tony has the habit of dropping his son (toddler-Peter) into Bucky's lap. Toddler-Peter loves it and loves Bucky. Bucky is at first flabberghasted, but quickly accepts that he is Peter's favorite (and Tony's too).
The first time it happens, Bucky very nearly drops the kid.
It’s only been a few days since Bucky’s arrived at the tower, fresh out of weeks of intensive therapy and trigger removal sessions, and he’s still wary and nervous around most people. Hiding away in his and Steve’s apartment is counterproductive to his recovery, though, at least according to Bucky’s therapist, and so he’d reluctantly let Steve drag him upstairs to have dinner with his friends.
Which had been noisy and chaotic, but not too bad. But now that everyone’s done, conversation is flowing freely, people are laughing and yelling over each other—and throwing leftover bread rolls, in Clint and Pietro’s case—and Bucky is starting to get twitchy. It doesn’t help that he doesn’t actually know any of these people in more than passing, and has no idea what the hell they’re all talking about most of the time, either.
He’s slowly inching his chair away from Steve, trying to be stealthy about it as he plans his route of escape, when something warm and wriggly is plopped into his lap. For a second, Bucky freezes, but then instincts he doesn’t remember having kick in when what turns out to be Tony’s kid suddenly lurches forward, and nearly brains himself on the edge of the table.
“Careful,” Bucky murmurs, pulling the kid back a little.
The kid squirms around at the sound of his voice, losing interest in whatever he was trying to do, and grins up at Bucky, big and toothy. “Uh! Uh!”
He reaches out towards Bucky’s beard, cooing softly as he clumsily pats at Bucky’s chin.
Bucky makes sure he has a good grip on him, before looking up helplessly. Stark is already walking away into the kitchen, though, and no one else seems to think anything about this is weird in any way.
“Bah, bah, bah,” the kid babbles, and then promptly jams his fingers into Bucky’s mouth.
The proud look on the kid’s face startles a quiet, amused huff out of Bucky. He pretends to bite the kid’s fingers, which makes the kid screech with laughter, and kick his little legs against Bucky’s stomach.
Bucky smiles, unable to help himself.
It’s the middle of the night when Bucky shuffles into the communal kitchen, yawning and bleary-eyed, heart still racing from dreams he’s terrified are actually memories. Distracted as he is, it takes him a moment to notice Tony, leaning against the counter with Peter in his arms, and looking at least as exhausted as Bucky feels.
“Oh, thank god,” Tony breathes out when he sees Bucky. He quickly crosses the room, and holds Peter out to Bucky, stifling a yawn of his own. “Hold him while I finish his bottle?”
As if on cue, the microwave dings. Bucky takes Peter, who’s frowning grumpily, and climbs up onto a stool at the breakfast bar. “What’re you doin’ up in the middle of the night, lil’ man, huh?”
“Uh-aah!” Peter complains, smacking a little fist against Bucky’s arm.
Bucky nods along seriously. “You don’t say?”
Peter grumbles, and turns to scowl in Tony’s direction. “Baba.”
“I’m coming, I’m coming,” Tony says, sitting down across from them, shaking a bottle of formula.
As soon as he sees it, Peter starts making grabby hands for it. Tony hands it over with a chuckle and an eyeroll, and Peter practically snatches it out of his hand, eagerly sucking the nipple into his mouth. He sighs around it, eyes fluttering, and leans back against Bucky, his fluffy hair soft against Bucky’s chest.
Tony’s knee is pressed against Bucky’s as he watches Peter drink with a small smile, and Peter’s a warm, pliant weight in Bucky’s lap, his free hand curled into Bucky’s pyjama pants.
“Yes, you are absolutely right, munchkin,” Tony says as he perches on the edge of the table, Peter on his hip. “Bucky should take a break.”
Bucky tries to look annoyed, but he’s biting back a smile. “Can’t. Gotta finish this before class tomorrow.”
“I’ll proofread and go make coffee,” Tony decides, getting up again. “Switch.”
He doesn’t wait, just plucks the tablet off the table, and sets Peter down in Bucky’s lap in exchange. Then he walks away, humming to himself while he scrolls through Bucky’s essay.
Peter tips his head back, smiling up at Bucky. Bucky sighs, and smiles back automatically. “Your father,” he grumbles, half-hearted at best, and drops a kiss on Peter’s forehead.
Bucky takes it to mean he agrees.
In his defense, Bucky’s dozing on the couch when Tony waltzes in, spots him, and comes over to put Peter down on his chest, so Bucky really can’t be blamed for blurting out, “What ‘bout me?” when Tony presses a kiss to the top of Peter’s head.
Tony blinks, eyes wide, and Bucky can actually feel himself blush up to the tips of his ears. But then Tony leans back down, his cheeks a little flushed, too, and brushes his lips across Bucky’s, light but lingering.
When he straightens up, Tony looks dazed, and his voice is rough when he says, “I’ll go order us some dinner.”
Bucky waits until Tony’s rounded the corner before he allows himself to fist pump.
Peter watches him, grinning gummily.
Everyone in the room, Avengers and reporters alike, turn at the sound of Peter’s shriek. The nanny shoots Tony an apologetic look, but Tony just shrugs, smiling indulgently. At the sight of his father, Peter starts squirming in the nanny’s arms to be put down, and the instant he’s feet touch the floor, he’s off toddling towards Tony.
Or, so Bucky thinks, until Peter keeps going right past Tony, coming to lean against Bucky’s shins. “Papa, up,” he demands, and Bucky complies on autopilot, lifting Peter up to stand on his legs.
Peter’s smiling, wide and happy, and Bucky leans in to kiss his cheeks, making him giggle.
Someone gasps, which makes Bucky realise how quiet the room has turned otherwise. When he looks up, the entire focus of the assembled press is on him and Peter.
Swallowing hard, Bucky risks a glance over at Tony, heart in his throat. But Tony’s still smiling, big enough to make the corners of his eyes crinkle, looking almost impossibly fond.
He puts a hand on Bucky’s leg under the table, giving him a reassuring squeeze, then faces the reporters again. “You know the rules, no pictures of Peter’s face unless you want to get your paper sued into oblivion. So. Any questions?”
The room erupts into noise.
Bucky hides his giddy grin in Peter’s hair, and puts his hand over Tony’s, squeezing back.
