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After initially finding out that the kid was lactose intolerant, Tony started doing everything in his power to help Peter avoid dairy. He stocked three kinds of plant-based milks at the compound—soy, almond, and cashew. If he was ordering pizza for team training nights, he would always make sure to have non-dairy pasta and salad options on the side. Chips and pretzels were served with hummus or bean dips rather than sour cream based ones, and Tony even tried out a vegan cheese version of his mother’s beloved lasagna recipe.
All these precautions would have likely been very effective, if only Peter wasn’t such a little shit.
At first, Tony assumed the kid just made a mistake. That was what he figured when he shuffled into the kitchen at one a.m. on a training weekend to discover the teenager standing with his back to the entrance, rifling through his cabinets.
Tony stood in the doorway, arms crossed over his chest in amusement. “Looking for something?”
Peter startled and spun around, eyes wide. “Whoa, what are you doing up, Mr. Stark?”
“Insomnia’s a bitch,” Tony scoffed. “But I could ask the same about you. Shouldn’t you be wiped from your training session with Cap earlier?”
Peter’s stomach growled loudly in response, causing his unusually pale cheeks to flush slightly.
Tony raised his eyebrows. “Are you hungry? If you need a snack, try the fridge.”
With a small groan, Peter snaked an arm around his middle. “Uh, no thanks,” he said with a grimace. "I'm not feeling so great, actually."
“Stomach ache?” Tony guessed.
Peter looked embarrassed, but nodded anyway. “I didn’t mean to bother you, I just was seeing if you had anything down here I could take for it.”
“You mean like Pepto, or...?” Tony asked with a frown.
Peter shook his head. “That doesn’t usually work very well. May has these like, enzyme pill things that sometimes help...?” he said hopefully.
Tony quirked his head in thought. “Pepper might have something,” he mused. “She’s fully on the herbal supplement bandwagon.” He crossed the kitchen over to a drawer next to the fridge and opened it to reveal a few dozen small bottles.
With some assistance from FRIDAY, he quickly identified the most-likely-to-be-helpful candidate—some kind of natural probiotic—and dosed out two pills for the kid.
“Thanks,” Peter muttered before knocking them back with some water. “Ugh. I’m never eating ice cream again,” he moaned.
Tony’s forehead wrinkled up in confusion. “When did you get ice cream?”
Peter gave him a pained smile. “Uh… after training? Clint took me out—he said someone should celebrate the fact that I laid out Cap twice.”
“Yeah, I thought so too,” Tony said with a huff. “Which is why I served everyone those vegan eclairs that I special ordered because, you know”—he shot Peter a pointed look—“they don’t have dairy.”
“He, uh, he said someone should celebrate it with a real dessert,” Peter mumbled.
“I’m hurt, Pete,” Tony mocked.
Peter’s gaze dropped to his feet. “If it makes you feel any better, I got Stark Raving Hazelnut.”
“Why would it make me feel better to have my name attached to your gastrointestinal distress?” Tony asked sarcastically.
Peter huffed out a quick laugh. “Sorry.” Suddenly he winced and pressed a hand to his stomach. “Ah. Cramp.”
“It’s alright, kid,” Tony scoffed. “I think you’re being punished enough.”
X
At the next Avengers team dinner, Tony stood in the buffet line behind Peter, watching in horror as the teenager covered his pasta in Alfredo sauce. “What the hell, Peter. I got the marinara one especially for you.”
“I had some of that already and it was great, Mr. Stark!” Peter said earnestly. “It’s just been like, forever since I had actual alfredo sauce.”
Tony blinked at him. “Right...” he said slowly “...That would be because you’re allergic to it.”
“Technically it’s not an allergy,” Peter argued, sprinkling parmesan on top of his fettuccine. “An allergy would require an autoimmune response. We learned that in freshman year bio.”
Tony rolled his eyes. “Fine, intolerance, whatever. You’re still gonna get sick.”
“I’ll be fine if I only have a little bit.”
X
A mere thirty minutes later, Tony was having déjà vu.
“Peter, I swear to God…” he began.
Peter gave him a sheepish grin. “Okay, I know what you’re gonna say, but—”
Tony spread his arms out dramatically. “There is literally half the dessert table here full of things you can eat, and yet you pick the cheesecake? Why?” he demanded.
Peter gave him an incredulous look. “Because it’s cheesecake, Mr. Stark,” he answered as if it were the most obvious thing in the world.
Tony scoffed, “Yeah, key word there, cheese.”
Peter gazed longingly at the towering fluffy white dessert balanced on the serving spatula in his hand. “But it’s so good.”
Tony ran an exasperated hand over his face. “Kid, think this through. I’m begging you.”
Peter let out a resigned sigh as he let the piece of cheesecake tip onto his waiting plate. “I have. I’m sorry.”
Tony raised his hands in mock surrender. “Alright, it’s your funeral. But I don’t wanna hear about it later.”
“You won’t—I promise,” Peter assured. He picked up a fork, and, making eye-contact with Tony the whole time, brought a bite to his lips. “But I gotta do it, Mr. Stark.”
X
A few hours after dinner, Tony spied Peter emerging from the restroom, pale and sweating, arms wrapped around his stomach.
“Uuugh Mr. Staaark…” Peter whined upon seeing his mentor. He was making a pouting face, but the smallest hint of a grin was playing at his lips. “My tummy hurts.”
With a snort of amusement, Tony held out a bottle of water to the teen, who took it gratefully. “I’m sure it does. Was it at least worth it?”
Peter thought for a moment as he sipped the water. “Almost,” he finally decided. He hummed to himself. “Now if the cheesecake had had whipped cream on it…”
Tony let out a long sigh. “Why? Why do you do this to yourself?” he implored.
Peter locked eyes with his mentor. “Mr. Stark,” he said solemnly, “some nights you just gotta face God and walk backwards into Hell.”
“NO YOU FUCKING DON’T, PETER!”
X
Tony was just finishing some updates on DUM-E when FRIDAY alerted him to the fact that Thor was urgently approaching the workshop doors. Given he wasn’t a usual visitor, Tony looked up curiously.
“Stark, you must come quickly!” Thor’s voice boomed. “The Falcon and young Man of Spiders seem to have ingested some kind of poison.”
Tony’s heart dropped. “What?” Peter and Sam had been poisoned? “How?” he asked sharply. He dropped his tools on the workbench and immediately hurried toward the door. “What kind of poison?”
“I am not certain,” Thor replied. The two men strode quickly down the corridor. “But it appears only to affect mortal men as I myself have consumed the same beverage and yet I remain unscathed.”
“Did you call in a med team?” Tony demanded.
“A healer?” Thor questioned. “Nay, but Banner had arrived just as I left to seek you.”
Tony instantly breathed out a sigh of relief. Sure, Bruce may not be an actual medical doctor, but his seven PhDs are certainly worth something. “Okay, good. What symptoms are we talking about here? When did this start?”
“It came on about an hour after consuming the beverage. They both appear to be in a fair amount of pain, and their bodies seem to be working to expel the contaminant,” Thor reported. “There is a foul odor about them as well, as though something inside is dying.”
“Jesus…” Tony swore, breaking into a jog for the rest of the way to the common area.
When he arrived, the scene wasn’t quite the picture of imminent peril that Thor had painted for him. On one couch, Sam was laying flat on his back, one arm hugging a pillow to his stomach while the other arm was extended upward so that his forearm rested over his eyes. On the couch next to him, Peter was half sprawled out, half propped up against the cushions so he could sip from a can of Sprite. He looked a little green.
Bruce, looking calm as ever, was lining a small trash can next to Peter with a fresh plastic bag.
“What’s going on here?” Tony demanded, stepping into the room. “Thor tells me they’ve been poisoned.”
Bruce let out a quick snort of laughter. “You could say that. Self-inflicted, but sure.”
“Excuse me?” Tony raised his eyebrows.
“Mr. Staaark…” Peter moaned from the sofa. “Did you know there’s no such thing as a milkshake on Asgard?”
Tony just blinked at him.
“I mean, imagine going your whole life without ever tasting a milkshake,” Peter went on, his tone just bordering on a whine.
“That’s just not right, man,” Sam groaned in agreement.
Tony glanced at the three, large, empty tumblers on the table nearby, their insides coated in what appeared to be milkshake residue. He looked back over his shoulder to the kitchen area and spied a blender sitting out on the counter.
“I can’t believe I’m seeing this,” Tony deadpanned. He shot Sam a glare. “And now you too?” he accused.
“Blame genetics,” Sam grumbled. “Did you know seventy-four percent of African Americans are lactose intolerant?”
“Rhodey isn’t,” Tony quipped.
“Well hooray for Rhodey then,” Sam muttered irritably into his arm. “Lucky bastard.”
“I do not understand,” Thor spoke up, frowning in confusion. “Have these men been poisoned or not?”
“Yes,” Peter groaned, clutching his stomach.
Tony rolled his eyes at the dramatic kid. “It’s… complicated,” he replied to Thor. “They’ll live, and with any luck, they’ll be deterred from future idiotic behavior for about a week. Or five days if I order pizza on Friday.”
“This was about justice for the Prince of Asgard,” Peter mumbled. “We die like men.”
“Men with tummy aches,” Tony pointed out.
Eyes still covered by his arm, Sam held up his middle finger. “We die like lactose intolerant men,” he amended.
With a hum of agreement, Peter promptly leaned over and vomited into the trash can.
As Bruce moved in to rub Peter’s back while he heaved, and Sam got up to make another trip to the bathroom, Tony threw his hands up in the air and turned on his heels.
“That’s it,” he muttered as he walked out. “I have officially given up.”