AN: Civil War did happen, but they made up enough to live in the tower together. Peter doesn't know what happened in Siberia. Only Tony knows that Peter is Spider-Man.

3rd Person POV

Peter had interned for Tony for a couple of months already when he found an odd file on his table in the lab, with his name on it. Opening the file, Peter discovered blueprints for a miniature arc reactor, like the one in Tony's chest. It showed how to connect and disconnect the reactor in his chest, in order to change it. The weirdest thing in the file was a ten-digit passcode and forty-five marked locations, all of which were in a wall in various rooms of the tower. Peter still committed the file to memory, believing it to be useful some day.

However, Peter wasn't expecting that day to come anytime soon. It was only a couple of weeks later, after a particularly tough mission. Tony, though he didn't admit it, had taken a hard hit to the chest, which caused his chest plate to fold in on him, and broke his arc reactor nearly in half. The man didn't say anything, secluding himself in the lab almost immediately after arrival. The spiderling had figured that something happened between Tony and one of the other Avengers, so he vowed to go to the lab after changing into more comfortable clothes and grabbing some ice cream and blankets.

Needless to say, every Avenger, Peter included, was startled and nearly scared out of their mind when Friday made an emergency announcement, stating "Boss is down in the lab. Immediate medical assistance is needed. Boss is down in the lab, immediate medical assistance is needed."

Peter ran, using every ounce of speed he had to get to the lab, barreling through stunned Avengers, and not even bothering to use the elevator, webbing through the stairway instead. The door to the lab was open, Friday knowing that Peter would've torn it off its hinges had it been closed, so the spiderling had easy access to the unconscious Stark.

Stark had collapsed, falling out of his chair and landing on his side, resulting in Peter turning the man onto his back. It was then that Peter noticed the arc reactor was split in half. He knew that was what kept the man alive, and immediately thought of the file he'd seen on the thing. Suddenly, the marked locations and ten-digit code made sense. They were locked locations of spare arc reactors.

Remembering that one of those locations was in the lab, Peter ran to it, discovering a pressure plate in the wall, which did a quick biometric scan before opening, revealing a safe that Peter quickly input the code into. Just as he grabbed the arc reactor and turned, he saw Steve about to perform CPR on Tony.

"STOP! You'll make it worse!" Steve, who was shocked by the unfamiliar child's out burst froze long enough for Peter to shove him away from Stark, Peter taking his place. The boy gently lifted the broken reactor, quickly assessing it and connecting it to the spare once he had determined it was safe to do so. Subconsciously holding his breath, Peter waited for his father-fig - mentor to regain consciousness.

It was nearly a full minute later that Tony abruptly sat up, taking in a large gulp of air. Peter breathed a sigh of relief as he squashed the urge to hug the man, unsure of whether or not it would do more harm than good. He heard similar sighs of relief from the Avengers gathered in the lab behind him.

"Glad I left that file for you, Underoos. I would've died had I not." By the shocked gasps from the Avengers, minus Natasha, Peter deduced that the others hadn't known about the reactor's true purpose unlike Peter.

"I'm glad, too, Mr. Stark." Before the aforementioned could respond, Captain America butted into the conversation.

"Why didn't you tell us? This is vital information pertaining to your life. You should've told us, what if this had happened and the child wasn't here? Speaking of which, why do you trust a child more than us? Why is he even in the tower in the first place?" Peter then realized that, in his mad dash to help Tony, he had forgotten his mask in his room.

"Rogers, you have no right to ask those questions after what you did in Siberia." Peter knew something was going on, and after Tony flinched away from Steve when the man took a step towards him, Peter had enough.

"Don't come any closer to him," Peter said, inserting himself between Tony and Steve, the former fighting off a panic attack while the latter laughed at the seemingly weak teenager.

"Son-" Peter interrupted him, "Don't call me son. You're not my father." Steve sighed, barely repressing his anger.

"Child, get out of the way. This is none of your business and you shouldn't even be he-" This time, Steve was interrupted by a repulsor blast purposely missing his head by a quarter of an inch. This shut the Captain up, though he casted a furious glare towards Tony, which was met with a Bat-glare-level one from the billionaire. It seemed that Stark had used the last bit of his energy to do that, his legs giving out. Before he hit the floor, Peter caught him, shifting Tony into a bridal style hold, aiming to carry him to his room as he was exhausted from surviving without his arc reactor for twenty minutes.

Despite the fact that Peter was holding one of his teammates, Steve decided to attempt to attack the spiderling. It didn't work, Steve finding himself webbed to the floor with one of Peter's specialized webs that were made to hold super soldiers or others with enhanced strength. As Peter moved to exit the lab, the other Avengers parted like the Red Sea, realizing who exactly the teenager was. The only unfazed Avenger was Natasha, since she already knew the spider's identity somehow.

Ten hours later, when Tony had awoken and made his way to the common room, was when Peter realized how much trust Tony had placed in him. It was evident by Tony answering Steve's previously asked questions.

"I didn't tell any of you since I didn't know if I could trust you all. The only ones who knew of the arc reactor's purpose were Rhodey, Pepper, and Peter. If Peter hadn't been there, one of the others would've. Anytime my reactor fails, an alert is sent to Rhodey, Pepper, and Peter's phones. I trust Peter because the kid is like a son to me, and is one of the only ones to not betray me, and, if you didn't already realize, the kid's Spider-Man. I bet he's worthy, too." Tony had only answered the questions because the super soldier was still webbed to the floor of the lab, as Peter had "accidentally" selected the formula that lasted twelve hours instead of two.

"You're like a father to me," Peter whispered as he gently hugged Tony, not wanting to injure him further. The man only wrapped his arms around the teen, furiously ignoring the tears welling up in his eyes and the way his heart swelled with happiness. If a happy tear or two trickled down his face, the Avengers didn't say anything. After Tony had told Peter what had truly happened in Siberia, it wasn't officially mentioned why Steve had moved out of the tower, but a certain spiderling might've possibly had something to do with it.