Tony knew that everyone teased him about being overprotective of Peter, and he didn't want to be one of those helicopter parents, especially since he wasn't even Peters actual parent, but he couldn't help it. The kid was like a magnet for trouble, and no matter how many rules and safety nets Tony laid out, Peter still went happily marching into danger, every time.

Tony did his best to protect him, but some things can't be kept away with trackers, webs, and curfews.

"Peter, are you feeling okay?"

The teenager looked up from his sandwich, legs swinging as he sat on the edge of the building, where he and Tony were perched for a post-mission snack.

"Yeah, why?"

Tony frowned at the lines and numbers scrolling across his vision in his Iron-Man suit. Karen had notified him that something was off about Peters vitals, but couldn't pinpoint what, exactly, was wrong.

"Did you get hit at all?"

Peter put his sandwich down and frowned. "No, I stayed away from them and just threw my webs; they never even touched me. What's wrong?"

Tony wasn't sure, that was the problem. Thankfully, it didn't seem to be urgent and Peter really did seem fine, but the heart rate scrolling across his vision was wonky and uneven.

"It's probably just a glitch in the suit, but Karen thinks your vitals are off, so finish that and we'll go see Bruce."

Peter groaned and rolled his eyes, as Tony sent the information to the compound to be ready for when they arrived. He knew why the kid was annoyed to be going, but heart abnormalities were not something to brush off.

"It's just to be safe, Peter."

Tony really wished it had just been a glitch in the suit. But, when Bruce saw the suit readings he frowned, swiping through the data on the screen next to the hospital bed he had Peter sitting on.

"What is it?" Tony really didn't want to hear the answer, because he could tell by the look on his friend's face, that something was wrong.

Peter looked between the two men, getting more nervous as Bruce pulled Tony a little bit away to talk to him. Not that, that would work, since he had enhanced senses anyway.

"Peter, put your headphones in." Of course, Tony would remember.

The teenager did as he was told but watched the two through the window, as they went to the next room to talk.

Bruce closed the door behind them, and did his best to stall, only making Tony more nervous.

"It could be nothing, I mean, we don't really know much about how Peters abilities affect his-"

"Bruce, stop, just spit it out."

The doctor sighed and wrung his hands in front of him, anxiously.

"His heartrate is irregular, it's called an arrhythmia, and usually I wouldn't really be worried because he seems fine but his blood pressure is too high, even though he's just sitting there. I want to do some more tests and figure out exactly what's causing this."

Tony looked behind him, through the window to where Peter was watching them, with those wide eyes. He turned back to Bruce. "Is this serious? Do we need to call his aunt?"

The doctor hesitated, but nodded, shoulders sagging. He'd always hated delivering bad news.

Tony didn't want to tell her, because May Parker was just as overprotective as he was, and he didn't want her to feel as sick and worried as he did. He wanted so badly to believe that Peter would be fine, and the tests would come back clean, but that kid had always attracted trouble wherever he went, and he could almost feel the bad news coming.

She came quickly, though he told her there was nothing known yet, and the tests hadn't even begun, and they sat with Peter through every scan, X-ray, MRI, EKG, and whatever else Bruce subjected him to. And then they sat there, in front of Bruce's desk, holding their breaths, waiting for the news.

"He has what's called dilated cardiomyopathy, or DCM, it's when the left ventricle is enlarged and weakened, and since that's the hearts main pumping chamber, it lessens the hearts ability to pump blood. He probably didn't even know anything was wrong, it often doesn't present any symptoms at all, and although he seems okay now, it can be very serious."

Tony felt like throwing up. Peter's best super power had always been his heart, and now there was something wrong with it.

May had a hand over her mouth, muffling her voice slightly as she spoke. "What does that mean? Is he going to be okay? What do we do to fix this?"

Tony was already picturing Peters face in his mind, and how it would fall when he told him he couldn't be Spider-Man anymore. But then Bruce spoke, tone noticeably brighter than before.

"This sort of diagnosis, in any other fifteen-year-old, would mean big lifestyle changes, but Peter's body can take far more than other kids can. I don't know how his enhanced healing is going to effect this, but Peter will be fine."

May let out a sigh of relief, but Tony shook his head. "His heart doesn't work properly, you can't actually be suggesting we just leave this alone. He can't continue to be Spider-Man with something like this."

His mind was already racing with awful images of Peter having a heart attack in the middle of a mission, but Bruce just adjusted his glasses, unfazed.

"We aren't going to just forget about this, Tony, I will be prescribing him a few medications to keep his blood pressure in control and other symptoms that might come up. And I'll be keeping a close eye on him to see how this progresses, but he isn't actually unwell, he can keep doing what he's doing, and be perfectly fine."

Tony knew that Bruce was the expert, but he couldn't wrap his head around the idea of just letting Peter run into danger, with a heart that didn't work properly.

"You said this could be serious? Shouldn't he be taking it easy?"

Bruce gave him a sympathetic smile, and on anyone else it would have been condescending, but on Bruce it just looked gentle. "Almost everything is easy for Peter. He's young, fit, and active, and he has super strength and enhanced healing. He can catch a car with his bare hands and not even break a sweat, so, as long as he feels okay and doesn't take any damage to his chest, he can do everything that he was before. People with these sorts of heart conditions still lead active lives, in fact its encouraged that they do. We'll keep an eye on his heart and his health, but he will be fine."

May looked relieved, wiping at her eyes before standing and shaking the doctors hand. "Thank you, so much. I'm going to go see Peter."

Tony wanted to believe that the teenager would be okay, but he couldn't let it go, he couldn't do nothing. So, despite his aversion to being the helicopter parent, he would be.

…

Peter slipped his suit on, returned after Tony tweaked a few things, and smiled as Karen greeted him.

"Hello, Peter."

The teenager slipped out his window, ready to get back to his nightly patrols, after spending a week doing tests and medication trials with Dr Banner. He felt fine, and thankfully May and Tony were beginning to believe that he was.

"Hey, Karen. It's really good to have you back."

"It's good to be back. How are you feeling? Any symptoms to report?"

Pete sighed, rolling his eyes as he swung to another building. "I'm fine. I should have known Tony would do something like this."

Karen continued, pleasant voice doing nothing to make the questions less annoying. "Have you taken your medication today?"

Peter was so sick of being asked that. "Yes. Can you stop asking these stupid questions and just tell me if there's anything in the city that I can help with? I'll take another bicycle theft at this point."

Karen hummed, stalling a little as the suit scanned its owner. "Your blood pressure, and heart rate are in acceptable range, so, yes I can do that."

Peter frowned, running across the top of a building, and looking out over the edge, at the people below. "Would you have not done it, if my heart rate was too high?"

She answered right away, making Peter groan in irritation. "Yes, Mr Stark has added new protocols to assist with keeping you safe, and monitoring your heart. If you had presented any unusual symptoms, he would be called and I would prevent you from 'diving headfirst into danger' as he put it."

"He doesn't have to worry so much; Dr Banner said I'm fine."

She still hadn't told him if there was anything he could be helping with, so he sat on the edge of the building instead, watching the tiny figures below.

Karen's voice was softer, as if she understood and wanted to make him feel better.

"I know, but he cares about you, and he can't help but worry."

That made Peter smile. "Thanks, Karen."

He knew Tony worried of course, and he hated when people worried over him, but it was actually nice to know they cared. And, he may have hated all the rules and extra precautions but he really did try to be careful. The diagnosis had scared him too, and he didn't want to stress out his heart too much, so, beating up bad guys and swinging around the city was easy, but maybe he'd leave catching cars, to people without heart problems.

Unfortunately, things don't always work out the way you plan, and trouble would always find Peter, no matter what he did to stop it.

They really needed to sort out some kind of security system for earth, because aliens just kept popping up like mushrooms. Tony hadn't wanted Peter to come, but they needed him, and he'd promised to stay back and fire webs from a distance. And, Peter had really wanted to keep that promise, but the alien was fast, and its super strength made it hard for anyone to stop it.

So, he'd fired webs and tried to trap it, which worked, until it knocked every Avenger back into the street and loomed over Tony.

The Iron Man suit was banged up and scratched, and Peter knew that Tony wasn't going to get to his feet in time to stop the meaty fist coming towards him.

The teenager flung out a web, and swung out in front of his mentor, kicking the ugly ass alien in the chest to send it smashing into a wall.

"Spider-Man, get out of here! You could get hurt!"

Peter took his metal hand and pulled him up from the ground, before firing another web and giving Tony a salute.

"You're welcome!"

He went back to running across roof tops, and swinging around the fight, keeping his distance, but what they hadn't yet seen from the gross, half burnt, too tall, raisin looking alien, was that it could fly.

Peter heard a round of surprised exclamations, through his com, including his own, as the thing looked apparently angry at being kicked into a wall by a baby spider. It stretched out its back, the ridges in its spine elongating until it had formed bony, wrinkly wings, and launched itself into the air. Right after Peter.

What was stupid about it, was that Peter had actually been following the rules this time, with a little lapse in rule following in order to save Tony, but he had gone right back to the side-lines when told to! He was being good! Yet, the alien still came towards him, as Tony tried to stop it before it touched his kid.

Peter saw it coming, and he tried to swing out of the way, but the beast was so fast he barely had a second before it was on him. He could hear the team calling his name, desperately trying to get there in time, but all they could do was watch as it's fist soared towards Peter's chest.

Tony watched it, watched the eyes on Peter's suit widen in fear, and thought 'god, no, why him'.

Alarms and warnings began screaming inside Tony's suit, monitors going crazy as Peter fell, as if nothing but deadweight.

Tony flew down, catching Peter and soaring off to the compound, as the alien screamed in pain, arrows, bullets, and a shield, hitting into it until it's body disintegrated, leaving nothing but a pile of ash and a smudge on a building.

Tony couldn't breathe, because Peter couldn't. Friday's voice was panicked, as she recited his injuries and suggested treatments. "He is having trouble breathing, his heart rate is too high, and his blood pressure is too low. He needs medical treatment immediately."

Peter was gasping, desperately trying to drag air into his damaged chest, and Tony flew as quickly as he could, finally crashing through a compound window and landing in the med-bay, cradling the teenager against him as he gently pulled their masks off.

He had never seen the teenager so scared. His mouth was open and gasping, as his hands pawed at his chest, trying to stop the pain.

Bruce ran in, immediately coming over to the patient as Tony lowered him to the bed. The Doctor started pulling Peter's suit off, yanking it down to expose the teenager's chest, and profusely apologising as Peter whimpered.

Tony stepped out of his Iron-Man suit and grabbed a stethoscope, whispering to the teenager as he pressed the head to his chest. Bruce had been teaching him everything there was to know about Peter's heart condition, so that he could help if needed.

"Shh, Peter, it's going to be okay. Just try to lay still and breathe." He didn't know if it was going to be okay, but he didn't know what else to say as Peter whimpered in pain, squirming under their hands, on the bed.

What he heard did not make him feel any better. Peter's heart was beating far too fast, and he had a murmur, a big one. Bruce had explained to him that a murmur was when blood was pumped through the valve, but flowed back into the heart chambers when the valve didn't close off as it should.

Tony froze, wishing he had imagined it. But Peter was crying softly under him, eyes barely open as he tried to breathe, and Tony couldn't deny it. He pulled the stethoscope away and turned to his friend.

"He's…there's a murmur."

Bruce looked up from where he was fixing an oxygen mask onto Peters face, and took the stethoscope form Tony's hands so that he could check himself. He had the same look on his face as Tony did; shock, concern, and dread.

"The valve is collapsing." Peter let out a strangled gasp as Bruce ran to the doorway and called for help. Tony could barely keep standing as nurses and doctors rushed in, crowding around Peter and yelling things.

Tony heard surgery being mentioned, as well as emergency transplants, and repairs, and his face crumpled, tears falling. And then he heard Peter's voice, weak and out of breath, shaking with fear.

"Tony!"

The sea of medical personnel parted, allowing Tony through to take the hand that Peter was holding out towards him. There were tears streaking down Peter's temples into his hair, as he gasped out words behind the oxygen mask.

"Please don't leave me!"

Tony squeezed his hand, and ran a hand through the kid's hair, brushing it back from his face as he forced a reassuring smile.

"I won't, I promise. I'm staying right here, Pete."

Peter looked up at him, those huge eyes afraid as his fingers gripped Tony's like a life line, the muscles across his chest contracting as he struggled to breathe. His mouth opened desperately as his breaths grew more rapid and shallow, until they were nothing but tiny gasps.

"Pete?"

And then his eyes closed, and his fingers grew lax.

Tony squeezed his hand, but got no response, heart hammering in his chest so hard he thought it might drown out his panicked words.

"Peter! No, come back, kid, come back!"

Arms wrapped around him, pulling him back from the bed, as he screamed, Peter's hand pulled from his to fall and hang from the bed.

Steve's voice met his ears, close and full of grief. "Tony, let them take him. Let them help."

He was being pulled away, and the nurses and doctors swarmed over the teenager, so that Tony couldn't see him anymore.

He struggled in Steve's hold, trying to get back to his kid. "No, I can't leave! I promised him, I promised I would stay. Please, he needs me."

But Steve's arms didn't relent, and he sagged to the floor as the gravity of the situation sank in. Peter was dying, and there was nothing he could do to stop it.

…

After four hours of surgery, and five days in bed in the med wing, Peter was alive and well, and recovering on the couch.

He was weak, and still sore, with a new scar down his chest, that scared Tony every time he saw it, but he was alive, and that's what mattered.

May had her arm wound him as they sat on the couch, under a bundle of blankets, watching movies. Steve was sitting on the other side of Peter, smiling when the kid nudged his arm. "Oh, watch this, this is the best part!"

Natasha and Clint swapped a bowl of popcorn and chips between them, as Sam quietly explained to Bucky everything that was happening in the movie. It should have been a nice night, but Tony couldn't let go of the panic every time he saw the heart monitor peeking out from under Peter's clothes, or the dark circles under his eyes.

The kid was healing quickly, as always, but he still seemed so fragile, and Tony couldn't trust that he was okay.

"Are you sure everything's working properly? Because I read about the complications and-"

Bruce patted his shoulder, as they stood in the next room, watching over their family. "Everything is working perfectly; the surgery went really well and he's getting stronger every day."

Tony rubbed a hand over his forehead, trying to get rid of the sick feeling he got everytime he remembered the way Peter had looked in that hospital bed, after the operation. He'd been so small under the wires, tube in his mouth, and pale eyelids closed. May had cried as soon as she'd seen him.

"I can't go through that again, he can't. I can't let him keep fighting and going out on missions, it's too dangerous. He can't be Spider-Man."

Bruce sighed and pointed to where Peter was laughing on the couch, as Clint tossed popcorn into the teenager's mouth from across the room, occasionally tossing some into Natasha and Bucky's hair just to make them throw a pillow his way.

"Are you really going to take this away from him? And what makes you think you can? Do you remember when I stitched up a wound he got on his shoulder, and told him he had three broken ribs, yet when you went to check on him a mere hour later, you found him helping an old lady carry her groceries to her car?"

Tony rolled his eyes and crossed his arms. "Yeah, he insisted he needed to help her, and that it hadn't hurt to carry them at all, and then when she tried to pay him for his trouble, he declined and told her that it was his pleasure to help." Tony found that his frown had turned into a proud smile by the end of his story, and Bruce nodded.

"He can't help but be a hero, it's who he is, and you can't stop it. He wants to help people, and no matter what you do to try to keep him from it, he will always find a way. It's what makes him so special, and why you can't help but love him."

Tony watched Peter giggle at the Avengers antics, Natasha and Bucky pinning Clint to the ground and tipping the bowl of popcorn over his head as Steve scolded them for making a mess, Sam complaining that they were wasting food.

The mechanic nodded, knowing Bruce was right.

"Yeah, and why no one else can either."

Tony Stark had never been good at loving things; he always managed to push them away or ruin them, and he couldn't bear to lose Peter. So, he became a helicopter parent, and did all he could to protect him.

He didn't want to give the suit back, because it was barely anything more than a red and blue invitation for the kid to get into trouble, but the smile on Peter's face was worth it.

That smile turned into a frown of confusion as the kid ran his hands over the suits chest.

"It feels different, it's stiff and thicker. What's it made of?"

Tony smiled proudly, crossing his arms and raising his eyebrows. "Steve and T'Challa are friends now, and he got some vibranium material to keep you safe.

Peter's eyes went wide as he looked at the suit, before looking up at Tony with a confused expression.

"I thought after that whole mess, you wouldn't want me doing this anymore?"

Tony shrugged, about to pretend like he was the cool, relaxed guy that didn't worry about anything at all, before rolling his eyes and relenting. "Bruce talked me out of banning you from it forever, but anyway that stuff is super strong, lightweight, and bullet proof, so it'll keep your heart safe when you're out saving people."

Peter smiled, excited out of his mind. "Fuck yeah!"

"Peter!"

The teenager spread a hand in front of him innocently. "What? It'll keep me safe and stop you from worrying. That's cool."

Tony smiled too. "Fuck yeah, it is."