Tony wasn't sure how he'd gotten to this point, and said so.
"I think you know the basic mechanics" Pepper snaps.
Tony stops pacing for a moment to glare at the woman who always stands by his side, no matter what happens, even when he contacts her during her vacation in the dead of night with his pregnant boyfriend—who just happens to be one of the most wanted super villains the Avengers have ever faced-and asked her to help him bring up the child.
"Stark I am going to kill you," A female Loki snaps from the bed, where she'd been in labor for the last hour.
"I didn't know you could get pregnant, did you know you could get pregnant?" Tony glares back at his sort of boyfriend.
"How did you even get pregnant anyway?" Pepper asks.
Both men glare at her, "I think you know the basic mechanics," Tony snarks.
"I am a god." Loki states, as if it were the obvious answer.
"Right."
It takes three more hours for Pepper and Tony to help deliver the baby girl. She's tiny and red and comes into the world screaming bloody murder. Tony winces as Pepper puts the screaming thing in his arms. Immediately the child quiets and looks up at him.
"What's her name?" Pepper asks the parents who are busy staring at this fragile thing they've somehow created.
"Uh-" They both shrug.
"Serenity," Pepper nods to herself, "Because it's something both of you could use, perhaps she'll get lucky."
"Pepper, she's going to be raised by the Avengers, chances are the only serenity she'll ever get is her name."
"Nevertheless I like it." Loki gives the shocked woman a small smile as she returns to being a he, "I believe you humans like middle names yes? Then it should be Endeavor, as that is what she is."
"Serenity Endeavor Stark?" Pepper asks, holding up a birth certificate.
"Yes." Tony nods his assent, handing the newly christened Serenity to Loki as Pepper discretely leaves the two alone. "She's your daughter as well, I recognize this."
"You should still raise her, as we agreed. Neither of our lives are stable, but at least there will people to protect her in your absence. With just me things would be—less certain." There is a moment of silence as Loki gazes at his daughter, "I do not know how my blood will affect her. Probably she will grow up more or less human."
"We'll cross the bridge of her heritage when we get to it. I'll tell her that you're her other father when she's older."
Loki's eyes darken, "Careful Stark, that sounds an awful lot like my childhood."
"I will never lie to her, or make her feel less for her blood," the other man snaps back.
There is a tense moment when Loki's hands start to tighten on Serenity, but then he relaxes, "care for her well Stark," he orders, placing his daughter in the hands of his lover and disappearing.
Tony Stark looks down at his daughter, who has remained silent throughout this whole exchange, looking at whichever of them that was holding her in the eye. Now she reaches up a chubby baby hand to presses it to his arc reactor. It drags a smile out him.
The smile lasts until he steps out of the birthing room to confront Pepper who has her 'what have you gotten us into' face on again and is holding a file of paperwork in one hand and a baby carrier in the other.
That's when the fact that he's a father hits him.
Pepper sees the moment reality crashes onto her friend, the way he gazes at Serenity with blind panic, she moves to swap him paperwork for the baby and proceeds to put her in the baby carrier. "You will be a better father." She whispers to him.
If Tony hears, he pretends not to, but does pick up the baby carrier as soon as Serenity is securely fastened. "I suppose we have to return and break the news now."
Pepper nods, having already checked out of the hotel and ordered the valet to bring her car around. "Your jet is waiting at the airport, we should be back in about 9 hours."
"Thank you Pepper. Seriously, this may be the most amazing thing you've ever done for me."
Pepper just smiles sadly at him, "You're a father now Tony. I never thought I'd see you with a child."
Nine and a half hours, one changed diaper and two tantrums later Tony and Pepper are stepping into the main lobby of the Avengers Tower where everyone has gathered to welcome them back—and find out what the big secret is.
Tony drops the bomb with his usual aplomb, "So guys I've got a kid; meet Serenity Endeavor Stark."
Luckily JARVIS is recording this, Tony is sure that the Avengers' faces will keep him entertained for years.
Clint and Natasha are just staring at him, eyes really wide—which is the same as jaw-dropping on regular people. Bruce is eyeing him like he's trying to figure out how drunk Tony is, then looking to Pepper for confirmation. Steve is gaping gobsmacked, eyes darting between Tony, the baby carrier, and Pepper. Thor is grinning.
"Congratulations my friend," the Norse God booms, "It is indeed a happy day."
Unfortunately his loud voice wakes up Serenity, who expresses her displeasure by displaying her lung capacity. Undeterred, Thor just picks her up out of the character and declares, "She will be a mighty warrior."
"Uhm yes, just be careful with her, okay big guy, baby humans are fragile." Tony's not hovering—much.
"Do not worry Man of Iron, I will keep her safe."
Tony manages a grin, but tenses when Natasha comes closer to inspect the little bundle, which is still wailing. She purses her lips, staring at the little girl, something a lot like longing in her eyes. Tony doesn't stop to think, just lifts Serenity out of Thor's hands and puts her in Natasha's arms. The look of wonder on the usually stoic woman's face makes him light up. Serenity ceases crying and does her funky looking at your soul thing.
Clint looks over Natasha's shoulder, "She's pretty, for a baby."
Tony grins, and looks expectantly at Steve, waiting for the Captain to ask the question on everyone's minds.
"Uhm, is Pepper the uhm mother?"
"I thought you and Pepper broke up" Clint chimes in, dangling a finger over Serenity—who is just giving him the baby version of the 'what the hell are you doing' face.
"Pepper is not the mother—"
"But the mother has given up custody." Pepper finishes for Tony.
"Right, so uhm, I'm not really good with the whole parenting thing, so, I was hoping you guys could like help with that. A bit. If you wanted."
There is a moment of silence, then Steve comes forward to clap Tony on the shoulder, "We'll try."
Thor's grin has faded just a bit, and his voice is serious, "I too will try and assist Man of Iron. I will look after her as if she were my own."
'Yeah… that's gonna go over well, considering she's Loki's kid.' Pepper and Tony share the thought via eye-message. You know that thing where people who've known each other for ever can talk with their eyes. Yeah. That.
Bruce backs away from the fragile baby, "What about the other guy."
"We'll be careful, you've got control unless we're fighting, and even I'm not reckless enough to bring my baby daughter to the battlefield," Tony gives the other scientist an easy grin, "It'll be fine dude, I trust you."
Natasha turns and plunks Serenity into the startled scientists arms, "Support her head."
"Uh, yeah."
No one notices the camera Clint has materialized from somewhere. Thus the first picture of Serenity is not taken by paparazzi, but rather by her Uncle Clint of her Uncle Bruce holding her looking a little timid. Clint pretty much never lets go of the camera, for which Tony is secretly grateful. (So are the rest of the Avengers, even if they do complain)
There is a media frenzy as soon as Tony announces Serenity's existence, every trash mag first trying to make the case for Pepper being the mother, then scouring the Earth looking for Serenity's real mom.
Nick Fury ranted a bit upon learning of Serenity, demanding to know who her real mother is. But Tony just keeps his mouth firmly shut, cuddles his daughter, and looks Nick dead in his eye. The director of SHIELD eventually leaves him alone.
Surprisingly it doesn't take the Avengers long to get the hang of caring for a baby. If Tony's holed up in his lab Clint and Natasha take turns getting up at night. During the day Serenity is either with Bruce in his lab, with Tony doing whatever he's doing, or with Thor. Steve looks after her while he cooks dinner.
Steve also starts a curse jar, and is actually backed up by Tony. Mostly it's Clint who forgets, and he usually pays by extra babysitting duties and having Tony take away all the fun arrows. All of this precaution doesn't stop Serenity's first sentence from being "Fucking Damn it all to Hell." It's very adorable in baby speak, but it does happen during a press conference and is caught on live camera.
Tony catches a lot of flak about it, but he shrugs it all off, pointing out that it's very advanced, so of course his baby's a genius.
Somehow all the robots love the little girl. JARVIS has even been caught playing all sorts of songs in her room throughout the night, and Dummy never drops her bottle. Mostly the humans –and god- prefer to take care of Serenity themselves, but an extra pair of –robotic—eyes never hurts.
After Loki forgives Tony for the very painful birth, he begins to visit the tower in secret, sometimes for sex with Tony, but just as often to watch his daughter sleep.
Thor returns to Asgard once informing his father and mother that he will remain on Earth until Loki is captured again. While the All-Father is not pleased, he softens when he learns of his adopted grandchild.
Serenity walks early, prompting Tony to set up new protocols to keep interested little fingers out of dangerous places. Like the lab.
As soon as Serenity starts talking 'Tasha and Clint start teaching her languages. Thor chimes in with Norse, but mostly leaves teaching to the two super spies.
Serenity ends up fluent in English, Russian, Latin, Romanian, Norse, Spanish, French, German, Hindi, Arabic, and Chinese. Tony retaliates by teaching her programming. Steve is just lost, so he teaches her how to cook. (Steve being the only Avenger even slightly capable in the kitchen)
When she's six, Serenity steals her Uncle Clint's bow and arrow and hacks her way into the range. She only tries to fire one arrow before Clint comes running, alerted by JARVIS, but it's enough to convince her over-protective father to allow her to start training.
Luckily Serenity doesn't take all the training to heart, as she meets the hulk up close and personal at age nine. Somehow this ends up with her playing catch with the big-guy. Tony is not amused, but Bruce finds it hilarious.
Despite his worries, Tony is a great father; he always has time for his little girl. Serenity is homeschooled up until age ten, at which point she throws a fit and—backed up by Steve—campaigns to be allowed to go to public school. Tony agrees, grudgingly, and terrorizes the press into letting Serenity go to school in peace.
Serenity does grow up wondering about her parentage. She's bright enough to see through Tony's dancing around the subject and Pepper's flat out refusal. She finally figures it out when she's 13, after a particularly fun fight with Doombots.
Most villains learned pretty quickly to leave Serenity alone. One, she was usually guarded by ten shield agents if the Avengers were fighting, two, she was dangerous in her own right, and three, the Avengers will fuck you up if you so much as look at her wrong. Loki sort of avoided the whole issue. Of course, he'd been less and less of a threat to the world since he started sleeping with Tony on the regular, but when he did cause mischief, he mostly kept it away from his daughter.
This is part of what lead Serenity to figuring out that Loki was her father. The other two parts were the fact that she looks like a perfect mix of Tony and Loki, growing up with glowing green eyes, brown hair, and a slim build. And then there was the day she sort of accidentally froze some Doombots. With magic.
Now, Serenity is definitely a genius. She's been helping her father with his suit for years, and helped Bruce with all sorts of experiments, but she's also taken the time to read up on Norse mythology and learn from her Uncle Thor about what's true and what's not.
So, when she freezes the hell out of a Doombot, she realizes that something's a little funky. And then she accidentally mind controls one of Fury's little pet humans into letting her wander about Fury's office. And there's the levitating. So yes, Serenity's got some magic. Some very strange mix of Aesir and Jotun magic.
For her fourteenth birthday, Tony gives Serenity her own suit. Which, yes, flying around is fun, but ever since she figured out the magical half of her heritage, Serenity had been playing with mixing magic and technology, using vibranium and arch reactors. The end result is a pair of cuffs around her wrist, JARVIS enabled, and a series of thin vibranium plates she inserted under most of the skin on her torso with some magical tweaking.
When activated, the plates act as an armor far superior to even her father's suit. Serenity finds this out the hard way when she takes a tank round to the chest. Tony is less than pleased to see his baby girl hit, and is both horrified and proud when he realizes how she survived. JARVIS is as exasperated with his humans as an AI can be. Loki is hiding on a building grinning like a mad man.
And so Serenity reaches the ripe old age of sixteen. She ends up with three different sweet sixteen birthday parties. One for the media, one of Tony's grandiose affairs with beautiful clothes, too much to drink, and fun antics, one is for the few friends Serenity's made at school and around town, held in a club and kept quiet from the media, and one is family only.
Three weeks later Serenity breezes out of the elevator after school and drops her bag on the counter, snagging an apple from the bowl Steve always leaves out for her. "Hey JARVIS baby, where is everyone?"
"Your father and Captain Rogers are at a media event. Ms. Romanoff is in her room. Dr. Banner went to the store, but Agent Barton and Thor are in his lab."
"Well, bollocks, they're probably wreaking havoc." The teenager smirks at the memory of her last prank on Clint. "I'll go collect them. I'm thinking of trying that recipe for Lembas bread."
"You should know they're messing with Dr. Banner's latest experiment."
"Oh dear."
See, Bruce had been researching something to do with gamma rays and magic and dimensions, but Serenity had gotten a little bored with his version of the experiments—which has hindered by the fact that Bruce could not do magic—and had played with it a little. She just didn't understand what the little gadget actually did now.
"Maybe we shouldn't poke it big guy."
"I am sure it is not dangerous."
Serenity tried not to groan too loudly as she walked into the lab, "Actually Thor darling, we don't know what exactly that does, so yes, quite possibly dangerous."
"You are home Serenity!"
"Aye, that I am."
Thor wraps his adopted daughter in his arms, lifting her up off the ground, "How was school."
She shrugs once the god sets her back on her feet, "It was whatever, 'sup Clint?"
The archer looks a little guilty, "Boredom."
"You pranked my room again didn't you?"
"Yep."
"Awesome." She takes a bite of the apple and wanders over to the machine, resting an arm on it, "So yeah, this baby. I think Bruce was trying to create something that would allow us to travel between worlds, not unlike the Bifrost. But, yeah, it looks like we need to be able to harness the energy which you, Thor, know as magic."
"I'm sure Loki would know." Thor murmurs, sadness for his lost brother in his eyes.
It was a familiar sentiment. Loki may not be high on SHIELD's list of most wanted anymore, but he certainly wasn't getting cozy with the Avengers, Tony excepted.
Serenity shrugs off the momentary melancholy, "Perhaps, but at any rate, he's built this thing, but we haven't been able to test it. So. Don't poke it."
Clint grins, "But what about this," and taps one of the pieces of crystal gently.
Immediately there's a mechanical whirring as the machine spins to point at Serenity, who freezes. Nothing else happens, and all in the lab let out a relived breath.
"What did I just—"
The apple drops to the floor of the lab, Serenity no longer anywhere to be seen.