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This Is Your Heart (Beating Off the Atrophy)

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“Mr. Stark!”

“Dr. Banner!”

“Tony Stark!”

“Mr. Banner!”

Bruce blinks hard against the camera flashes as he shoulders past the reporters circling the tower.

“Dr. Banner, how do you feel about dating a man twenty-three years younger than you?”

“Did you know about the Iron Man suit before Mr. Stark’s admission?”

“Mr. Stark, what do you have to say to reports that Mr. Banner lived in Stark mansion for ten years?” one reporter calls out.

“It was thirteen, not ten,” Tony corrects, looping his arm around Bruce’s shoulder. He guides Bruce through the swell of paparazzi, letting him bury his face against wool of his suit jacket. Bruce sucks in a breath and forces himself to stay calm-- this is nothing they haven't dealt with before.

“Dr. Banner, are the allegations that you and Mr. Stark were romantically involved before he turned seventeen true?”

Tony ushers Bruce into a nondescript black sedan, and the muffled silence once the door shuts makes Bruce slump against the seat in relief.

“Happy, update,” Tony calls out. “Who leaked what, and why didn’t I know about it before we stepped into the circus?”

“It’s SHIELD, sir,” Happy says. The lines around his eyes are tight in the rearview mirror.  “SHIELD has been compromised, and your file was among those leaked.”



Chapter 1



Tony Stark is five when Bruce Banner moves into the Stark’s Fifth Avenue mansion.

Bruce is twenty-eight, old beyond his years, and tired of running.

He stands in the Starks’ decadent foyer with his duffle bag of earthly belonging and wonders what the hell he’s doing here. His tattered suit is more patches than original material, and his last haircut was seven months ago in front of a cracked bathroom mirror in Kolkata. Bruce hunches his shoulders as he faces his godparents, the instinct to make himself as small as possible overwhelming his urge to look presentable.

Maria Stark sweeps him into a wordless hug, and he presses his face into the crook of her neck, breathing in lavender and ink and the closest thing to home he’s smelled in three years. “We’re so glad you’re safe,” she says.

Her fingers catch in his unruly curls as he nods.

Bruce’s neck prickles, and he looks up from her embrace on instinct. A little boy is perched on the first landing of the oak stairs, tiny hands wrapped around the spindles and face pressed between them to get a better view of the proceedings.

Anthony, Bruce remembers. Last time he saw the kid, he was only an infant in his mother’s arms and Bruce’s world was a much simpler place. That was over four years ago, and he can still remember how quiet Anthony had been, grinning toothlessly as he grabbed for Bruce’s glasses.

Now, however, Anthony's old enough for his resemblance to Howard to be striking. He has the same unruly dark hair of Howard’s youth, but the most striking resemblance is in the fierce intelligence that sparkles in his brown eyes. It startles Bruce to see eyes that sharp set into a face so young and otherwise devoid of expression.

Then the boy catches his gaze and smiles, open and wide but equally sharp. A look of childish mischief replaces his bored expression as he holds one finger up to his lips in a shushing gesture. Bruce can’t help quirking a small smile back, the first smile in months he hasn’t had to force.

“You’ll be staying here for the foreseeable future, then?”

Howard’s words startle Bruce back to the present. He disengages from Maria’s hold and takes a steadying breath. “I- No, I have no intention of imposing on your hospitality for longer than necessary. I just need a few days to sort out things and plan my next move.”

Bruce knows they could afford it, but that isn’t the issue. He’s not going to become a freeloader, rich godparents or not. More than that, though, seeing Anthony drives home the facts: Bruce is dangerous, and a family home is no place for a thing like him.

Howard claps him on the shoulder bracingly. “I have enough contacts at SHIELD to be able to help out with your… situation, and Stark Industries’ resources are invaluable. I wish you’d come to me sooner.”

“You know why I couldn’t.”

“As a matter of fact, I don’t,” Howard says, turning pointedly. He strolls through the ornate study doors without looking back, leaving them ajarin what could either be invitation or just a lack of concern. Bruce stifles another sigh and hesitates, but Maria’s hand at the small of his back urges him forward.

“And Tony?” Howard calls from the doorway, “Go to bed.”

Out of the corner of his eye, Bruce sees Anthony pull a face before scampering up the stairs.

“He’ll be listening through the vents in three minutes,” Maria murmurs as she ushers Bruce into the study. “We haven’t found a nanny yet who can keep him in bed.”

A sudden series of coughs wrack her slender frame. Bruce reaches towards her automatically, but stops short of making contact, hand hovering just off her shoulder. “I’m fine,” she says from behind her hand. “I’m just getting over a bout of the flu.”

Bruce perches awkwardly on a red leather sofa as Howard pours three glasses of bourbon. He pauses, glancing at the amount in each before adding an extra measure to the third. Apparently satisfied, he claims that one as his own and takes a sip as Maria passes one to Bruce.

Howard cocks his hip against the mahogany desk. “When you wrote we honestly didn’t know what to expect. After three years of radio silence, I had to, ah, acquire a few SHIELD reports to even find out that you were still alive.”

Bruce stared down at his bourbon, and Howard continued, “I must admit, you look in much better health than I’d expected. Aside from a dire need for a new suit and a good meal, there doesn’t appear to be any physical deterioration. The way you spoke in your letters, I rather expected you to be a permanent shade of grass green.”

“It’s, better than it used to be,” Bruce says delicately. “I’ve figured out how to keep it locked down. Mostly. That’s the only reason I even considered coming back to the States.”

“Stark Industries R&D could always use a mind like yours. Open access to anything that could help you research a cure.”

“Howard, you know my situation. It’s not that simple. Even commuting in New York to get to the labs is dangerous for me.”

Too much stimuli. Too much noise. Too much stupid.

“Which is exactly why we’d like you to stay here with us. Maria and I have already discussed it. The basement level of the mansion houses labs that should be more than adequate for your work for SI and your own research.”

Bruce feels his pulse jump at the words and hurriedly takes a gulp of his drink. Howard says it like it’s so sure, like it’s a done deal that he’ll live here and work for SI, like Howard has actually even considered all the ways this could go wrong.

Dangerous. Killer. Monster. Out of control.

The words echo through his head, but instead of saying any of them, Bruce forces a smile. “I’m not going to be a freeloader. You probably get enough of that as is, and you’ve done more than enough for me. You took me in after my father-- after he--” Bruce chokes on the words, the memories too strong.

His father, yelling. His mother, dead. Him, helpless. The blood, the blood, the blood.

“It’s hardly freeloading when my company gets access to one of the greatest scientific minds of a generation,” Howard interrupts, calling him back to reality. Howard eyes him curiously but with none of the wariness Bruce knows should be there. ‘Science mode’ is practically written across his face. Maria, on the other hand, has her glass in a white-knuckled grip.

Bruce quirks a sad smile at her. “It’s the eyes, right? They’re damn creepy.” He’s seen them in the mirror before, electric green just before he blacks out with the transformation. “Like I said, I’m not safe to be around. You two have a kid now, a family you need to protect, and taking me in like a rabid stray isn’t the way to do that. I’m not thirteen and helpless with one parent dead and the other in an asylum. I’m an adult, and it was my own hubris that got me into this situation.”

“And it’s a situation in which I feel I can offer some assistance. The sub-levels are structurally engineered to withstand a direct nuclear strike on Manhattan. I think they can take you.” Howard straightens, moving into Bruce’s space. “That’s what you want, isn’t it? A place where you can withdraw, cut yourself off from humanity but still research how to save it, pessimistic futurist that you are?”

“I broke Harlem!” Bruce says, louder than he’d intended, and sucks in several calming breaths-- a touchstone of sorts he’d developed over the last three years.

Maria shifts, setting her glass aside and folding onto the sofa next to him. A gentle hand runs over his cheek, and Bruce can’t help leaning into it. It’s been so long since he’s felt even the most basic human contact, and her touch reminds him so much of being thirteen and safe for the first time in a long time.

“Stay,” she says softly, and he doesn’t resist when she pulls his head down to her chest.




Tony is also five when Bruce speaks to him for the first time.

Bruce has seen Anthony lurking around corners or being shuffled about by the nanny of the week, but he’s never spoken to him. The house staff have told Bruce about him, “genius” and “menace” being the most common adjectives used. Quite frankly, Bruce goes out of his way to avoid Anthony. Even after a month and a half of living at Stark Mansion, he is still adamant that he shouldn’t be here, especially not around a child.

So it’s a surprise when Bruce walks into the basement lab to find the young boy perched on a tall stool at one of the worktables, soldering iron in hand. The Whoplay softly in the background, and Anthony hums along slightly off-key.

Bruce stops just inside the doorway. “Hello,” he says, warily drawing out the word. His voice sounds rusty from disuse, even to his own ears.

Anthony looks up from the circuit board only briefly before dismissing Bruce’s presence. “Hey.”

“What’re you doing here, Anthony?” Bruce asks carefully. “Isn’t it a little late?”

“It’s only eleven-fifteen,” Anthony says dismissively. “And the nannies aren’t allowed down here.”

Bruce cautiously steps further into the lab. He’s read the articles that Maria secretly saves, but it’s an entirely different thing to see it up-close. Against his will, his feet carry him closer so he can peer over the boy’s small shoulder.

He watches, jaw slack, as Anthony weaves a gridwork of connections, tiny fingers masterfully manipulating metal and silicon.

Anthony is the first to break the silence. “You don’t like me,” he says, not looking away from his work. He doesn’t sound upset about it, just a bit miffed, like Bruce is an anomaly he can’t account for.

“I- I’m sorry, what?” Bruce fumbles.

“You. You don’t like me, which is dumb. I haven’t even done anything to piss you off yet.”

Reflexively, Bruce chides, “Language,” because that’s the easiest part of that statement to deal with.

Anthony does turn then, setting the soldering iron aside and looking up at Bruce in irritation. “What, ‘piss’? Not you, too. If I’m old enough to be left alone with power tools and molten metal, I’m old enough to swear.”

Bruce can’t help the concerned face he makes. “Yeah, well, just don’t say it in front of your parents.”

“Who do you think I learned it from, the maid?” Anthony rolls his eyes theatrically. “She swears in Spanish.”

Bruce stares, gobsmacked, at this boy with his young face, old eyes, and a smart mouth. Somehow, when everyone said ‘genius,’ he had heard ‘savant.’ Instead, Anthony’s speech and social skills seem almost as rapidly developed as his mind. He speaks more clearly than most other five-year-olds, and while Bruce suspects elocution lessons are part of it, there’s something innately off about his speech pattern.

Anthony stares back, unblinking.  “People find me disconcerting. I mean, it’s okay. I’m used to it.”

“That could be because you just used the word ‘disconcerting’.”

“Look, if it bothers you that much, don’t talk to me. Sometimes monastic silence is the unwilling lab partners’ best friend,” Anthony says with an exasperated huff that does, in fact, befit a five year old.

Bruce can’t help it-- he starts laughing, howling with it the way he hasn’t for years. It’s a ragged laugh, almost like he’s forgotten how, but it shakes his entire body and forces him to clutch the lab table for support. The young boy stares at him like he’s lost his mind, but that only makes Bruce laugh harder.

Monastic s-silence,” is all the he manages to wheeze out between bouts of laughter. It’s not even something that would normally earn more than a chuckle from him, but from a five-year-old it’s just too ridiculous. Not only is Anthony being sarcastic, he’s utilizing it for humor, by all accounts is something he should be at least three years too young for, and Bruce can’t help cataloging the information for later perusal.

After a moment, a suppressed giggle escapes Anthony, and then he’s laughing, too, high and boyish. “You think-- think I’m funny,” he giggles. “No one ever thinks I’m funny.”

“Yes, Anthony, I think you’re funny. And I’m not surprised no one does if you’re talking to people your own age.” Bruce says, straightening his glasses and running a hand back through his bangs. “And it’s not that I don’t like you.”

“Then why won’t you come near me?” Anthony wines, like Bruce is a shiny new toy being kept just out of reach. “And why do you keep calling me Anthony? It’s Tony. ‘Anthony’ is my great uncle.”

“Okay then. Tony, if you prefer.” Bruce drums his fingers against his leg and considers his next words, unsure how honest to be with a five-year-old. “It’s not safe for you to be around me,” he says at last.

“Mom wouldn’t let you stay here if that was true.”

“I’m dangerous,” Bruce confesses. “I’m not exactly good for anyone who values self-preservation.”

Tony looks dubious as he goes back to his circuits. “You don’t look dangerous.”

Bruce hesitates before saying slowly, “No, I suppose I don’t. But a lot of dangerous people don’t look dangerous.”

“That’s what Dad meant by your ‘situation,' right?” Tony asks, and then more intently: “Are you really one of the greatest scientific minds of your generation?”

Huh, Maria was right; he had been listening. Bruce scratches the side of his head. “Uh, I mean, it’s been said.”

“But is it true?”

“Yes,” he says honestly. Of course, there’ve been some bumps, but modesty aside, Bruce is well aware of just how capable his mind is.

“And you’ll be doing your research here? What on?”

“Gamma radiation, mostly, but there are also some things for the company your dad wants me to take a look at.”

Civilian applications only, he’d been promised. Working for a company with military funding still doesn’t sit entirely right with him, but Bruce can’t deny the good Stark Industries does in the humanitarian sector. Howard want him to look into remote clean water technology, and if his research is also used to get water to troops and not just orphans in Africa? Well, at least it’s not guns.

“I can still work down here, too, right? Every time I try to go somewhere else, I get in trouble for scratching the tables or singeing the carpet.”

Bruce hesitates. That… wasn’t part of his arrangement with Howard. Trying to worry about a kid while running tests hardly seems like a good idea. But then, this is Tony’s home first.

“I won’t get in the way, and I know proper lab safety and procedure,” Tony pleads.

And Bruce knows he can say no, knows that that’s probably what Howard expects him to do, but instead he says, “Okay. Yeah.”

“Good. Would you please tell the nanny that. She keeps saying I’m too young to be down here.”

“One thing, okay Tony?” Bruce waits until Tony meets his eyes and then points to the door. “If I tell you to run, you run. Got it? No standing around to watch what happens.”

Tony’s brown eyes are serious as he says, “Okay.”



Tony is still five when he convinces Bruce to leave the lab for the first time.

But then, “convince” might not be the right word.

“Come on!” Tony says, springing up from his chair, cereal forgotten.

Bruce looks from the New York Times spread out over the kitchen table and raises his eyebrows. “It’s seven AM, and I’m only on my first cup of coffee. It’s going to take a lot more than that to make me move.”

Tony points at the half of the newspaper he’d commandeered for himself. “The Museum of Modern Art has an exhibit on the art of the elements. It opened last week. Let’s go!”

Bruce takes a long drink of his coffee. “The MoMA? I thought you were more the Museum of Natural History type.”

“And I thought you were the tea type,” Tony says, snagging the mug from Bruce’s hand. He takes a sip and makes a face. “That’s really gross. What is that?”

“Decaf,” Bruce deadpans and tries to ignore how incongruent that gesture and joke are for a five-year-old. “Why don’t you ask Jennet?”

Tony scoffs. “Jennet quit last week. It’s Susan now, and she’s even more boring. Even if she would take me-- which she won’t-- she’d be impatient and wouldn’t enjoy it like you. She can’t even name all the elements; I checked.”

In the six months he’s lived at Stark Mansion, Bruce has found that one of the constants of life is that no nanny stays for more than three weeks. Ever. Before he’d gotten to know Tony, he assumed this was because the child was the stereotypical rich brat. “A terror” is what he was told, but now Bruce realizes that Tony is less a terror in the sense that he’s a spoiled brat and more in that things tend to explode around him.

A lot of things.

Sharing a lab with Tony has been far more eventful than Bruce ever anticipated. He’s taken to keeping a fire extinguisher within arm’s reach at all times, a fact that says way too much about his new normal.  And that right there is the crux of it: Despite the fact that their lab sounds like an ammunitions test site half the time, it never disturbs his equilibrium. There’s never any risk of Tony bringing out the Other Guy.

If there had been, Bruce would’ve disengaged from the situation, but it's almost impossible to get angry when he sees Tony’s chagrined smile and singed bangs through a cloud of smoke. He wishes too much that he’d had the opportunity to blow things up until he got it right when he was a kid, to experiment without consequence.

Bruce is rarely a fan of the women hired to care for Tony. It’s not personal, not really. He can sympathize with the women’s frayed nerves, he really can, but they way they act around Tony never sits right with him. Most of them treat him like a normal five year old, and worse still, some of them act like Tony’s higher intelligence means he must have lower social skills. It’s no wonder Tony gets bored enough to start blowing things up.

Bruce learned early on that Tony neither needed nor wanted to be talked to like a child. A quick way to make Tony storm out of the lab in a huff, Bruce found, is to dumb down his speech the way he would with other children.

Few of the nannies even try to understand how Tony’s mind works, which is even more the pity. Tony Stark has the most amazing mind Bruce has ever seen. Even at only five years old, Tony can challenge him intellectually and give him a new perspective on experiments.

The lack of stability bothers him most, though. In some bout of cosmic humor, Bruce has become the most stable fixture in Tony’s life. And Bruce knows it’s not his place to say anything against the revolving door of nannies, but sometimes he has difficulty holding his tongue.

That’s what perplexes him, if he’s honest. He understands Howard-- Howard was the hands-off type even when Bruce lived with the Starks nearly a decade and a half ago, but Maria always took time out of her schedule for Bruce. Bruce wasn’t her son, and she never tried to act as a replacement for his mom, but she still loved him and taught him how to trust again, how to channel his anger at life into his innovations.

That she’s so rarely around for her own son confuses Bruce, especially when Tony clearly cares so much for her. That much is evident by the way he talks about her. But Bruce is a guest in this house, hardly more than a temporary interloper, so he says nothing.

“Come on, Bruce,” Tony pleads, dragging the older man back to the present. “You’re going to wilt without fresh air.”

“I’m not a houseplant. And there’s nothing fresh about Manhattan air,” Bruce protests, but a smile tugs at the edge of his lips. Maria used to always say that to him when he spent too many days in a row curled in a corner of the library lost in his own head.

“Fine then. We’ll go to Central Park after.” Tony tugs on his wrist. “Please?

“And how, exactly, do you plan on us getting there?” Bruce covers his smile with a disapproving shake of his head. “I can’t ride the subway.”

“I’ve got money for a cab.”

“Of course you do,” Bruce says with a sigh and stands. “Well, that’s all I’ve got for token protests. You’re sure your parents won’t mind?”

“Dad won’t notice, and Momma’s out today.”

That’s not what he asked, but Bruce figures it’s the best he’s going to get. Realistically, they could be gone all day, and everyone would probably just assume they’re in the lab. Still, he scribbles a note on some scrap paper and leaves it on the counter. Because really, the nanny-- Janet? He’s forgotten already-- should at least know where her charge has disappeared to.

He changes into the only pairs of slacks he owns without frayed hems and makes a mental note to go shopping. As much as he hates the press of crowds, he has a stable income working for a Fortune 500 company, and he might as well dress like it when he’s in public.

Sometime and one slightly too eventful cab ride later, Bruce staggers out onto the curb of 53rd Street. “Do not ever say ‘step on it’ to the cabbie when I’ve got to ride with you, got it? Jesus, we’re walking back. I haven’t come this far to die in a cab on 5th Av,” he says as he tries to regain his sea legs.

Tony drags him by the hand up two flights of stairs, barely sparing a glance for anything else.

“Aren’t we at least going to look at the Warhols?” Bruce asks as Tony pulls him around a corner.

“After,” Tony says, intent on his target.

He leads them into a smaller partitioned area, and Bruce looks around in surprise. A different piece represents each element. Carbon is a glass box, barely larger than Bruce’s thumbprint, with a tiny “6” printed in the top center. A perfectly cut diamond shines inside at its heart. Argon is a set of purple neon lights reading “18”. Closest to them, a red balloon floats in front of a cream background, a neat black “2” printed on its face.

Bruce watches as Tony leans forward slightly, toes barely touching the black line on the floor. His brown eyes shine bright with excitement, and warmth blooms in Bruce’s chest. This was worth the cab ride from hell.

As they make their way through the rest of the gallery, Bruce tells Tony what little he knows of the pieces and their stories. Art history was never one of his strong points, but he’s had an elective or two on the subject. Once in a while Tony interjects with his own stories about the artists themselves at Maria’s fundraisers. The storytelling distracts Bruce from the crowd and the push of unfamiliar bodies against his.

When the honey-slow movement of tourists becomes too much and his chest starts to tighten with the feeling of being caged in, he steers them into a dark, cool room. The noise from outside is muted, and a projector cycles through a series of seemingly random black and white photographs. The click of the slide change is the only noise apart from the distant rumble of people.

The exhibit is empty apart from them, and for once Tony doesn’t rush him, apparently sensing Bruce’s distress. “Are you okay?” Tony whispers.

“Fine,” Bruce manages as he tries to get his breathing back under control. “Too many people.”

“Are you claustrophobic?”

“Something like that,” he says.”You ready to go?”

Bruce decides to make good on his threat to walk back to the Mansion despite Tony’s very vocal insistence that they hail a cab. They make it to 61st before he ends up on Bruce’s shoulders, tiny fists clenched in his hair like reins. The dark humor of a child riding on the back of a latent rage monster doesn’t escape Bruce. Maybe that should worry him, but despite his earlier bout of claustrophobia, he knows he’s got a lid on the Other Guy.

“You can’t actually steer me like a pony, you know that, right?” Bruce says resignedly when Tony gives a particularly sharp tug on his curls.

Tony doesn’t dignify that with a response. “Where’re we going?” he asks when Bruce veers off 5th.

“You said we could go to Central Park, and if I put up with Midtown for three hours, I’m getting my park.”

Rather than protesting, Tony clambers off his perch, managing to knee Bruce in the side on the way down.

He walks backwards down the path and motions for Bruce to follow. “Come on!” he calls as he trots ahead. “I know a spot.”

Bruce follows at a leisurely stroll, hands in his pockets and suit jacket folded over the crook of his arm, and takes a deep breath, holding it for a five count before exhaling. It was nice to leave the mansion, but Midtown makes him antsy. Maybe next time they could go to the Botanical Gardens.

Next time.

Huh. That… sounds like a bad idea, but now that he’s thought it, Bruce can’t shake the notion that there will be a next time, especially not as he follows Tony off the path towards a large formation of rock.

Tony scrambles up the side with the fearless zeal of youth, too young to be afraid of the height. His wild grin reveals a missing a tooth, and it’s maybe the first time he’s really seemed like a child to Bruce. The snarky boy who builds circuits seems so far removed from this child with arms outstretched for balance as he climbs across a crest.

“Careful,” Bruce warns.

“Come on!” Tony motions impatiently before disappearing over an embankment.

Bruce resigns himself to losing his last presentable pair of slacks and does his best to follow, knees scraping across the stone as he tries to find purchase. At the top Tony is already sitting, ignoring Bruce in favor of watching the people pass on the path below.

Bruce gingerly takes a seat next to him and listens as Tony begins to point out the various bizarre breeds of city dogs. He toes off his shoes and settles in for the long haul, enjoying a rant about the absurdity of corgis.

After that, weekly day trips to museums and libraries become  a part of their routine, and once more Bruce watches his new normal shift to fit around Tony Stark.