They've literally just arrived at the site of the incident when Tony hears a kuh-WHUMPH behind him and turns. He's briefly blinded by a burst of multi-hued light from around the corner of the nearest building.
The corner Steve just turned.
“Steve!” he shouts. “Are you hit?”
The only response he gets is a strangely high-pitched moan.
His heart rockets into his throat and he yells, “JARVIS, thrusters!”
“Iron Man, what is it, what happened?” Natasha demands and he ignores her.
The bizarre light seems to have broken up and fallen, glimmering on the pavement like glitter as he roars overhead. The HUD picks out a heap on the road ahead of him and immediately offers up information: heartbeat twice as fast as normal, stuttering; heat signature reduced by a third. Tony slams to a stop a few feet away and feels panic claw at the back of his throat.
It's Steve's uniform all right, but there's something wrong—it's crumpled like it's been gutted, emptied out.
But there's a heartbeat. Whatever happened, whatever's wrong, Steve's still alive. He can survive.
He can, he can; he has to.
“Steve!” he calls, and hears his own voice shake. The knees of the suit clang as he drops, hands sweeping over the uniform, afraid to touch.
It's so empty, god, what's left of him?
Is this going to be the time he has to go home without Steve?
“Iron Man!” Natasha barks.
“I don't know,” he snarls at her, “I'm trying to find out!” Then the heap of fabric shifts, bits of the light tumbling off and winking out. The shifting grows more violent, like something's trying to kick its way out—
Abruptly it hits Tony: quick heartbeat, lowered heat signature, empty suit.
Steve's been shrunk.
A tuft of blond hair appears at the neck of the suit.
“Jesus, Steve, you scared the devil out of me,” he says, reaching forward to help him pry his way out.
A round little head pokes through and Tony stops in his tracks, staring.
Not just shrunk.
His husband has enormous blue eyes, a cute little button nose, and freckles like cinnamon sprinkled over milk-white skin.
He's a child, no more than four or five.
Who looks at Tony in the Iron Man suit and immediately shrinks back a little, fear flickering across his face. Then eyebrows so blond and sparse they're practically invisible dive in toward the bridge of his nose, a scowl coming across his face. “Where's mama?” he demands. “Who're you?” He starts struggling again, trying to fight his way out of the Cap suit.
Tony stares, shock rooting him in place.
“Iron Man,” Natasha calls, and this time instead of coming from the comm in his ear, her voice is coming from the proximity audio channel. He whirls around and sees the rest of the team headed toward their position.
“Guys!” he blurts. “We have—uh, a situation.”
“Yeah, whatever the hell was fucking with the buildings is gone,” Clint says, peevishly. “The damage vanished about seventy seconds ago.”
“It was an illusion,” Thor says, “we are not clear on the purpose.”
Which, of course, is when tiny Steve manages to wriggle free of the uniform and bolts away, buck naked.
“Shit!” Tony says, “Steve, hang on, wait a second!”
“Steve?” he hears Natasha echo incredulously.
Steve, much to his relief, slows and turns back to look at him, eyes narrowed, ready to make a break for it in a second. “How d'you know my name?” he asks.
Tony's mind races. He could lie. Tell him he knows his mother. God, he can't lie though. Looking back at him is the same piercing gaze he's grown accustomed to—Steve will see through a lie in a second.
So instead he tells the truth.
He retracts the faceplate and Steve's eyes go wide. “I know your name because you know me, Steve.”
“No, I don't,” Steve retorts, but he doesn't sound certain.
“You do. You just don't remember right now. You had a really long nap.”
Doubt creeps into Steve's expression and his eyes drop to the suit, moving slowly over it and then over to where the others are standing and to the street beyond. A little bit of the fear comes back and his bony shoulders curl. “So...my mom's not here?”
Steve squats down, arms pulled tight around his knees. “So I'm alone?” he says in a small voice, and Tony's heart squeezes tight in his chest. Steve looks like he might burst into tears any second.
“No, no, you're not alone. I know you don't remember, but like I said, you know me and these are all our friends, Thor and Clint and Natasha. We're not gonna let anything happen to you.”
“How come—how come I don't remember?” Steve asks, gulping back shuddering breaths.
“Well,” Tony says, and hell, honesty's worked out okay so far: “we don't know. But we're gonna find out. Will you come with us? With me?”
Steve looks at him, eyes wet and wrenchingly sad, and then at the street around them, and the nearby Avengers. Finally, he nods.
Tony waves to the others. “Thor, buddy, gimme your cape, will you?”
“Certainly,” Thor says, and begins to unfasten it, paying no mind to the way Steve stares up at him. Clint scoops up Steve's discarded suit. Tony steps out of the Mark IL and Steve's jaw drops.
“Wow,” he whispers. “You go inside it?”
“Yep,” Tony says, and can't help the warm, fuzzy sensation he gets as Steve watches it close up, awe written all over his face. “Home,” he orders and Steve gawks as the suit takes off.
Tony kneels down. “Is it okay if I wrap you up in Thor's cape? You gotta be a little chilly with no clothes on.”
Steve sniffles and admits, “I kinda am.”
Tony takes that to mean he's got permission and swings the cape back around Steve's shoulders. “You mind if I pick you up for the trip home? The streets are pretty rough, I don't want you to cut up your feet.”
“Okay,” Steve agrees and Tony scoops him up, tucking the cape in around him in something vaguely resembling a toga.
“All right, here we go,” he says, and gets to his feet with Natasha's steadying hand on his elbow, feeling Steve's little fingers dig into his shoulders, holding on tight. He hugs Steve close. “We'll have you back to yourself in no time,” he murmurs.
Tiny Steve is a handful.
He hangs nicely in Tony's arms for about four minutes, and then can't seem to sit still any longer. He starts wriggling around, trying to see better and exclaiming over everything. He winds up draped over Tony's shoulder, his little toes kicking against Tony's ribs as Thor shows him Mjölnir to keep him from attempting to get loose completely.
The five of them detour into Macy's on their way back to the Tower. Natasha hangs back as they head inside. “I'm going to call Stephen,” she says.
“Good idea. Thank you!” Tony calls back.
“Who's Stephen?” Steve asks, pulling back over Tony's shoulder far enough to look him in the eye. “Mama calls me Stephen when she's mad.”
Tony smothers a laugh. “Stephen is a friend of ours. He'll help us get you back to your mom.”
“Oh. Gee, there are a lot of clothes here,” he says, arms curling around Tony's neck as he cranes to look deeper into the store. “I never seen so many.”
“Too many if you ask me,” Clint mutters.
“I want you to pick out some you want to wear, okay?” Tony says as they head into the racks of boy's clothes.
Steve presses back against Tony's shoulders, staring at him wide-eyed. “I can have some?”
Tony nods. “Can't have you wandering around in a cape-toga.”
For a minute, Steve seems to have been rendered speechless, and he looks around at the rows and rows of clothing, struck dumb by the opportunity presented to him. Then he points and they're off, looking at everything in sight, Steve talking a hundred miles an hour, exclaiming at all the different pieces. Clint and Thor volunteer up several outfits, which Steve provides scathing reviews of. Tony's chest aches with smothering his laughter.
After nearly twenty minutes of looking, Tony says, “All right, bud, we can't do this all day. You gotta make a choice.”
Steve looks agonized, but he considers for a minute and then points at the Iron Man shirt and the little pair of jeans Clint's been carrying around for ten minutes. “Those ones.” Then he blushes and adds, “Please.”
Tony grins. “You got it.”
Thor helps him get Steve into the new clothes and Steve presses up against the mirror in the dressing room, drinking in his reflection hungrily. Picking out shoes is thankfully somewhat quicker. Steve sees the light-up soled sneakers and falls instantly in love. He tries half-heartedly to show more interest in some of the more subdued shoes, but Clint pulls out the light-ups and says, “Don't you think these ones are cool?”
Steve curls up in Tony's arms, shy for the first time. “Yeah, but I can't have those.”
“Sure you can,” Tony declares and waves a hand. “Bring 'em, Legolas.” Steve looks like Christmas has come early.
When they check out, Tony hefts him up onto the counter so the clerk can scan the tags in the clothes. Steve just about chatters her ear off, pointing out the thumb-loops on the sleeves and playing with the shiny plastic circle over the arc reactor on the chest.
“Let me get these tags off,” the clerk says. “Hold still, honey.”
Steve, however, doesn't seem capable. Tony cups the back of his neck while she snips the tag from the shirt and Steve's motormouth keeps running, words muffled in between their bodies, undeterred.
“Thank you,” Tony says, when she's throwing the tags out and Steve chirps, “Thank you!” The clerk smiles.
With his feet protected by the new shoes, Steve goes running ahead of them toward the entrance of the store, jumping and stomping to make the shoes light up.
“God,” Clint says, “I expected a quieter kid.”
“Nay,” Thor says, “our Steve is a reserved man, but that is by design, not by accident.”
“True,” Tony agrees. “Get him going about the right thing and he'll talk your ear off.”
When they emerge from the store, Natasha is crouched down next to Steve with a bemused expression as he shows off all of the intricacies of his outfit again, one small hand petting her hair. He's breathless with excitement.
Or at least, that's what Tony thinks at first.
As they head back toward the Tower, Steve's breathing doesn't improve. He's still talking, but every so often he has to stop mid-sentence to take a deep breath. When those deep breaths start to whistle, Tony gets worried. He stops and kneels down.
“Hey, Steve, are you having trouble breathing, buddy?”
Steve glances at him, but doesn't stop rambling about how he can't wait to show his mom his new clothes, circling around Tony and dragging his hand over Tony's body. Tony catches him as he comes around. “Hey, this is important, okay? Are you having trouble breathing?”
Fidgeting with the plastic circle on the shirt, Steve stares at the ground. He's still struggling too much to breathe, but Tony forces himself to wait.
“...yes,” Steve admits finally, reluctant. Then quickly, “But I'm okay.”
“Nope, sorry,” Tony says, “not being able to breathe is not okay. I'm going to pick you up now, so we can get back quicker.”
“No!” Steve protests, but Tony picks him up anyway.
“Guys, let's move, I think he's having an asthma attack.” He gets Steve settled at his hip and they pick up the pace.
Steve starts to cry, his tiny fists battering at Tony's shoulders. “N-no, I'm fine, let me down!” He tries to keep going, but between the sobs and his already tight throat, he can't breathe well enough to talk anymore. Tony's heart flutters anxiously behind his breastbone.
He breaks into a run when he hears Steve's breathing stop all together for a moment. Behind them, he can hear Natasha demanding that a medical team meet them in the lobby.
“It's okay,” Tony pants, “I've got you.”
Steve sucks in a rattling gasp and Tony puts on an extra burst of speed, barreling through the doors of the Tower. The medical team steps out of the elevator ahead of them and after that, everything dissolves into chaos.
At one point, Steve's lips turn blue.
For a minute, Tony's terrified it's too late. Steve is going to die as a five-year-old because he wasn't paying close enough attention.
But they get him on oxygen and a nebulizer and the blue fades to pink, the wheeze to silence.
Steve is tiny and paler than ever in the MedBay bed, laying lethargically in a heap of pillows, face covered in plastic mask and tubes.
“He's going to be all right,” the doctor says finally, stepping back. “He'll need rest and to take it easy, but he's going to be fine.”
Tony moves to sit by the bed, hands still shaking. Gingerly, he brushes the damp hair plastered to Steve's forehead aside. His eyelashes flutter and open a sliver.
“Hey,” Tony whispers. “You're going to be okay, Steve.”
“She's not here, honey, I'm sorry.”
Steve starts to cry.
Tony slips onto the bed, pulling Steve against his side and holding him close. “Shhh, shh, you're all right,” he murmurs, running a hand up and down Steve's back in long strokes. The mask fogs up and Tony has to pull it aside to wipe Steve's nose. When he tries to put it back, Steve resists. “I know you don't like it,” Tony says, “but you gotta keep it on until the doctor says so.”
Eventually, Steve wears himself out and falls asleep, tears still trekking down his cheeks.
Exhausted, it's not long before Tony's out too.
He wakes later to the bed shifting under him. “Mnh, Steve?” he mumbles blearily.
“What are we doing in the MedBay, Tony, are you hurt?” he hears, and then feels familiar hands on his face. Tony's eyes snap open and he turns onto his hip.
“Steve,” he breathes, drinking in the sight of his face, square jaw and sharp cheekbones back where they belong.
Steve's hands trace the length of his arms, eyes traveling over him critically. “What are we doing in the MedBay?” he asks again. “Are you hurt?”
Tony scrubs at his face to wake himself up. “No, no, I'm not hurt. You got turned into a kid. You had an asthma attack. I thought—I thought, Jesus, I thought you were going to die like that. Your lips turned blue—”
“Hey,” Steve says, hand curling around Tony's neck, “it's okay, I'm fine.”
Tony presses a kiss to his mouth, hanging on to him tightly. “As cute as you were, I'd really rather not do that again, okay? God, I'm glad you're okay.”
That's twice in one day he's been afraid he'd seen Steve for the last time. It's going to be awhile before he feels like he can leave Steve on his own. Thankfully, Steve doesn't seem to mind all that much.
“I love you,” Steve murmurs, and Tony curls up against his side.
At least today, they're going to be okay.