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Kate was hanging upside-down, exercising, when she got the call from America. “Look, I need you to get to my apartment fast. No questions. And, uh, pick up some diapers on the way.”
While Kate was pretty used to weird requests coming from America (a long list indeed), that was definitely one of the weirdest. When she got to America’s apartment, she immediately laughed at her friend when she realized America was bouncing a crying baby on her knee. “Yeah, yeah, laugh it up,” she grumbled. “Look, I think she needs a change. She smells bad enough, anyways. Did you get the diapers or not?”
"I did," Kate said, "but do you have any baby supplies? Hold on, I’ll be right back."
The second trip out took some time, but eventually she returned with baby wipes and food. “You’re lucky I know how to take care of a baby. Where the hell did you find a baby, anyways?”
"I rescued her," America said, following Kate as she brought the baby and the supplies over to a table and started changing the baby’s diaper. "Her parents were so busy smoking crack they didn’t even notice. I didn’t know what to do, so I brought her here."
Kate pursed her lips. “You could have brought her to the police.”
America snorted. “And what happens after that? Her parents show up and probably take her home. Anyways, that’s why I called you, Princess.”
Kate sighed as she finished changing the baby (who seemed to be a girl) and asked, “Do you know her name?”
"Grace," America said. "I think. The mother was getting pissy about her."
"Well, part of it must have been their reluctance to replace her diapers, if that day-old thing is any indication." Kate wrinkled her nose at the old diaper. "Seriously, can you put it in another dimension or something? It smells so bad."
America laughed. “Don’t worry, big strong America will get rid of the stinky diaper, Princess.”
"Oh, f…rick you, America."
"Nice save in front of the baby." America wrapped the diaper in a bag and threw it in the trash. "How old do you think she is, anyways?"
"I dunno." Grace looked like she was about to start crying again, and Kate quickly figured out she was probably hungry. "A year. Maybe. Probably less. Am I supposed to be a baby expert?"
America said something in Spanish that sounded like cussing. Kate said, “Not in front of the baby, America. We don’t want her to see her mommies fighting.” America opened her mouth again and Kate interrupted, “We need to feed her. So unless you magically started producing milk…”
It took a while, but eventually they got the baby fed, and then they laid her down in America’s bed. Kate stayed around, and she and America talked out a plan. They’d keep the baby for the night, then take her to social services and explain the situation. And hopefully not get arrested.
They wasted the rest of the day, and then Kate went to sleep with the baby while America took the couch.
Kate was, predictably, woken up in the middle of the night by the baby’s crying. She quickly determined that the baby was older.
At least two years older.
They’d put her in a onesie that was now constricting Grace. Kate quickly grabbed a pair of scissors and cut it open, at which point she noticed that the diaper was also tight. She made it looser and the little mutant (was she a mutant? Kate didn’t even know) smiled at her, reaching out with both arms. “Mama!”
"Uh." Kate looked out into the other room, where America appeared to not be awake. "I’m not your mama, kid."
"Mama," Grace repeated. She looked like she was about to start crying again. Quickly, Kate scooped her up into her arms.
"I don’t know what you are," she said quietly, "but I hope you don’t grow any more tonight, Grace." She fit Grace into a shirt that was several times too big for her and then said, "Come on, let’s get back to sleep."
"Mama," Grace replied happily, shuffling close to Kate as she fell asleep.
The next morning, Kate woke to a girl of at least five, who squirmed until she was sitting up, still swamped by the shirt she was wearing to sleep. “Mama,” she yawned. “Hungry, mama.”
Kate looked her over. Several years older, hair much longer (and looking a lot like America’s), eyes shaped a lot like Kate’s. She picked Grace up and said, “We’ll get you something on the way, sweetie.” She carried Grace out to America and shook her awake with a foot. “We need to get her tested for the X-gene.”
It didn’t take long. Grace was negative, of course.
While Grace was happily munching on the breakfast they’d gotten her, dressed in clothes they’d also gotten on the way to the only doctor who wouldn’t charge them. Who happened to not be a doctor, and was also their friend Billy, who sat and chanted “DoesGracehavetheX-gene” while the rest of them waited.
Billy shrugged helplessly at them. “I don’t know. If you want me to figure out what she is or where she came from…”
"It’s fine," Kate said. "I think she’s our daughter." She gestured between herself and America.
Both Billy and America were looking at her like she was crazy. “Okay,” America said, “first of all, I think I’d remember making a kid with you, Princess. Second of all, why? You’re the only one she calls ‘mama’ and I’m the one who rescued her from her parents.”
Kate rolled her eyes. “Well, maybe if you knew how to take care of a kid at all…”
America’s jaw dropped. “I’m nineteen, Princess! And I’m not exactly the mothering type.”
Billy squeezed both their shoulders. “Okay, how about we just… shelve that argument. She does kind of look like both of you, America.”
"I am way too young to have a kid, chico." America frowned, looking over at Grace. "Maybe we should bring her to the Avengers. We don’t know what she is."
"No!" Kate punched America in the arm, resisting the urge to run over to Grace and hold her close. "Look, I’ll keep her at my apartment until she stops growing. Billy can look into what she is, and we’ll get the Avengers involved if we have to. But only if we have to."
Billy said, “As far as I can tell… she’s a normal kid, except for the aging thing. But if she was actually yours somehow, Kate, I don’t think it’d be out of the question for her to be… special. Maybe an alternate dimension version of you two or something?”
"No," America said decisively. "That isn’t possible. There’s only one me."
Grace said, “Mama? I’m bored.”
Kate got up and picked Grace up. “Why don’t we go hang out with Uncle Teddy, huh, kid? Then we’ll stop by the store. You know what you like?”
"Of course," Grace said. "Can I have some milk?"
Kate and Grace stayed at Billy’s place for a while longer, while Kate talked to Billy’s parents and explained why she couldn’t just hand Grace over to social services. They gave her the advice they could and gave her a few of Billy’s old toys. Eventually she took Grace back to her own apartment, detouring by the store to get more food, and got her settled in. Grace tired herself out somewhere around three, and Kate set her down for an hour nap. She quickly went out and got some bigger clothes in case Grace grew again, and when she returned, America was standing in the middle of her apartment.
Kate had several questions, beginning with how the hell Kate got into her apartment, but America asked her own question first. “Why the hell did you leave her alone?”
Kate frowned. “Excuse you, you wanted to hand her over to the Avengers! Besides, she’s napping, I was just going out to get her some bigger clothes.”
A few moments later, she heard Grace getting up. She was an inch taller, and she smiled widely when she saw both America and Kate. “Let’s watch TV, mama,” she said as she grabbed both their hands. “Uncle Teddy said TV is really fun, I wanna see it.”
They watched cartoons the rest of the day, with Grace sprawled across their laps. She kept her head in America’s lap, her curly hair spreading over America’s jeans. At nine she fell asleep again, and Kate put her in her bed before going back out to America. “I don’t think she’s our daughter,” America said instantly. “But you’re my friend, Princess. And if you’re gonna do this, you’re gonna need help.”
Kate couldn’t help her smile. “Really? So we’re just friends, raising a child together. Beginning our family in a completely platonic way. I thought you were out of the closet, America.”
America blushed and grumbled, “Shut up. Where am I sleeping?”
Kate gave her the couch, and took the nearby reclining chair for herself. She was woken up in the middle of the night by a small body crawling on top of her, and she carried Grace back to her bed. “Nightmares?” she murmured. Grace just nodded. “Well, just hold on a second and I’ll grab America, and we’ll cuddle with you. The nightmares won’t be able to get you then.”
America grumbled when Kate roused her, but followed without comment. They snuggled Grace between them, and all three slept peacefully.
In the morning, Grace wasn’t that much bigger. She’d grown maybe a year in her sleep, and her hair was a lot longer. Kate set her down in front of a mirror and brushed and cut it. First to her shoulders, then to chin-length, on request. America went out and got her a toothbrush, along with some kid’s toothpaste. Kate taught her how to brush her teeth, and then they went out. Kate grabbed some teaching books, since she figured it’d be easier to homeschool Grace than figure out some way to enroll her somewhere. America was finding Grace some books she liked.
After book-shopping, they visited Billy again. He did a few incantations and said, “I think she’s slowing down, on the aging thing. And I, uh, sort of asked the Scarlet Witch if it was possible Grace was somehow yours.” He blanched when America and Kate both glared daggers at him. “Look! If anyone was gonna know anything about it, it’d be her. And I didn’t actually mention any names. She said that if you two got together in the future, and then something magical happened, your baby’s soul might have ended up in the present day, or something. I don’t know, mostly all I got was that she’s just as annoyed with time travel as everyone else in existence.”
"So what you’re saying," America said slowly, "is that I actually have a child with Kate."
"I’m saying it’s… possible," Billy muttered.
America pursed her lips, looking over at Kate. “Well, there’s definitely worse people to have kids with.” Something occurred to her suddenly and she sat straight up. “One of us has to adopt her, Princess. We don’t have any legal right to keep her.”
Kate gasped. “Oh, shit.” She covered her mouth as soon as she realized what she said. “Please tell me Grace is still watching cartoons with Teddy.”
Billy laughed. “Grace did not hear you cuss, Kate. And I know you didn’t ask my opinion on this… but you should probably show her to the Avengers. If you need backup, Teddy and I are here for you, always.”
"Thanks, Billy," Kate said, leaning against him. "What do you think, America?"
"I think I’m not sure I wanna raise a child with a straight girl." America rocked back and forth and sighed. "You’re the one she likes to call mama, Princess. It’s your decision. I’ll tag along either way."
Kate frowned and was about to say something like ‘You are one-half of her probable-parentage and you should start acting like it’ when Teddy appeared, carrying Grace. “She said she was feeling sleepy and passed out,” he murmured. “I tried to wake her up but I couldn’t.”
That decided it for Kate. She smoothed Grace’s hair away from her face (not even bothering to wonder where all her motherly feelings were coming from) and said, “Teddy, you carry her. We’re going to visit the Avengers. America?”
"Coming," she sighed. "I’ll carry you, Princess."
Grace woke up on the way, and America flew closer to Teddy so Kate could pet her hair and say, “We’re just going for another visit. We’re flying!” and Grace nodded and fell asleep again.
When they reached the Tower, they went straight to the top levels. They didn’t stop to say hello to anyone (although Billy did wave at the Scarlet Witch, who followed them) and went straight to Tony’s lab where, predictably, he was working on something. Kate set Grace down and said in a rush, “I think this is my daughter with America somehow and when I first saw her she was a baby and then she was older and then she got older again when she was sleeping and now she’s asleep and won’t wake up and I’m really scared!”
Tony blinked, obviously processing his way through all that. Then, “Aren’t you a little young to be a parent, Kate?”
"Piss off," Kate said. "Just help her."
"I can’t do both, but…" Tony looked closely at Grace. "Huh. She does kind of look like she’s yours."
Billy and the Scarlet Witch talked quietly, and Kate kept an eye on them and on Tony, who was attaching Grace to a machine that soon began to show her brain activity. He watched it for a minute and said, “The good news is, this is just normal REM sleep. She’s probably dreaming about fluffy bunnies, assuming she knows what fluffy bunnies are. The bad news is that this is just normal REM sleep, which means that her problem probably isn’t medical. You say she was aging rapidly?”
"Yeah," America said. "When I picked her up, she was a year old, if that. Then she was five."
Tony hummed. “Is she a mutant?”
Kate shook her head. “Billy magically tested her for the X-gene. She’s definitely not a mutant.”
"Wanda?" The Scarlet Witch looked up from her son for once. "Do you think you could help me out here? Check her out with your magic?"
"Of course," she said, smiling kindly at Kate and America. "Just give me a moment."
She hovered over Grace and concentrated. A few minutes later she said, “She is definitely not of this time. She is from the future, and some sort of accident caused her to travel back and regress into the form of a baby. I assume her rapid aging is her way of returning to normal. I can sense magical potential in her, as well as other power I can’t determine.” Wanda smiled at Kate. “Let her rest and she should be fine.”
It took three days for Grace to wake up. Three days during which neither Kate nor America left her side for any longer than a bathroom break or to eat, and there was always one of them next to her. Neither of them talked about it.
Billy and Teddy visited twice, to make sure they were okay. Wanda (as she insisted they call her) visited once, to check on Grace. Kate’s sister visited on behalf of their dad, but soon got a headache as Kate explained the situation and left.
When Grace finally woke up, she stretched and mumbled, “Mama?”
Kate was holding her hand instantly. America was in the room a second later. “I’m here,” Kate said. Grace looked around and smiled happily when she saw America. “We’re both here,” she added unnecessarily.
Grace stretched again and said, “I wanna see Uncle Billy and Uncle Teddy, mama.”
Kate laughed. She couldn’t help herself. To Grace, it was probably just a long nap. “Does that have anything to do with the way they give you sweets, Grace?”
Grace’s cheeks puffed out and then she said, “No.” She looked so serious that for a second she was a carbon copy of America.
Kate ran her hands through Grace’s hair, which had grown in her sleep again. “Well, okay. But first we need to get you a haircut.”
As Kate cut Grace’s hair, she looked her daughter over. Six, she decided eventually, and a half, if that.
"Go find something that fits you," Kate told Grace. "Then we’ll go over to see Billy and Teddy. Maybe after we can go shopping."
"Okay," Grace said happily, pulling her down to kiss her on the cheek before running off.
America grabbed Kate by the jacket and pulled her in for a kiss. “I’m sorry,” she said a moment later. “I don’t know why I did that, Princess. Usually don’t steal kisses.”
"It’s fine," Kate said, ignoring the way her lips were tingling and that was sort of high on her hottest kisses list. "It, uh." She forced herself to smirk at America. "It wasn’t terrible." She tugged herself out of America’s grip. "Maybe we should go, now? Grace is probably waiting."
"Of course." America grabbed Kate’s hand, which made Kate smile. But only a little.
They spent at least two hours every day with the Avengers. Grace hated it, but Tony insisted on running tests on her until he was sure she was stable, and they were helping Kate formally adopt Grace. One day he promised her a whole stack of cookies if she let him put a few needles in her. He did a few major inoculations and then drew some blood.
As Grace was happily eating her cookies (washing them down with milk helpfully supplied by a passing-through Captain Marvel), Kate gave Tony a sample of her blood. America was more reluctant to give up her blood. Finally Tony said, “Look, I promise I’ll just compare it to Grace’s. I won’t look at your blood any more than I need to confirm or deny your parentage. I’ll get Carol to throw it into the sun afterwards.”
Captain Marvel leaned against the doorway. “Can’t we find a disposal method that doesn’t require me to fly to the sun?”
America’s lips twitched in a half-smile. To Tony, “All right. But not even a drop of my blood gets left over, Stark.”
"I solemnly swear," Tony said seriously before jabbing the needle into America’s arm.
" ‘I solemnly swear that I am up to no good’ isn’t something to inspire confidence, Tony." Kate pulled her daughter onto her lap and smirked at him when he frowned. "What? I read Harry Potter."
Tony shrugged. “Yeah, well, it’s just what came to mind. I am up to plenty of good, I promise.”
He was distracted by science after that, and Captain Marvel said, “Anyways, I just came back to tell you two that your friends are here to see you. I can watch TV with the kid if you want to talk to them in private.”
Kate squeezed Grace. “What d’you say, Grace? Want to hang out with Aunt Carol for a while?”
"Yesh," Grace said with her face full of cookies. She gathered her remaining cookies and milk and followed Captain Marvel. America looked like she wanted to follow, but Kate dragged her to where Billy, Teddy, and David were waiting.
"Tommy’s arguing with Quicksilver," Billy said, looking embarrassed. Kate would be embarrassed too, with a brother like Tommy. "They might be racing."
Teddy laughed. “Who are you trying to kid? They’re definitely racing.”
"They’re definitely racing," Billy amended with a smile at his boyfriend. They gazed lovingly at each other until Kate snapped her fingers in front of their faces to get their attention. "Oh. Yeah. Right. The Runaways asked for our help in L.A., something about a time travel incursion. I figured we’d come pick you guys up and teleport."
Kate considered it. She said, “Someone has to stay here with Grace.”
America nodded. “You stay here, Princess. I’ll K.O. a few people, be back in time for lunch.”
Kate grinned, unable to keep the teasing tone out of her voice. “You promise, Princess?”
In answer, America grabbed her by the back of her head and pulled her in for a kiss. Unlike the first time, Kate kissed back a little a little too eagerly, which made both of them laugh. “We’re trying that again later,” she murmured. “See you in a couple hours, America.”
America left with the rest of the Young Avengers, and a few moments later Kate found Captain Marvel floating upside down with a giggling Grace, who was squirming. “Okay,” Kate said, holding out her arms, “I think that’s enough playing with Aunt Carol for today, Grace.” Grace was gently lowered into her arms and she quickly latched onto Kate in her usual manner, arms tight around her neck and legs equally tight around her waist.
Grace started talking immediately. “We were watching this show it was really cool it had tons of fluffy animals and Aunt Carol said that having a cat was really fun and she said to ask if we could get a cat—” Kate frowned at Captain Marvel, who shrugged. “—and then Aunt Carol said she could fly and I really love flying so I asked her if she could lift me up with her flying like mama America does and she did and that’s when you came back!”
"Wait," Kate said. "Mama America?"
"Yeah," Grace said, looking at Kate like she was being silly. "I have you, mama, and mama America."
Kate almost laughed but she knew how strange that would seem to the others in the room. Instead she smiled happily at Grace and kissed her cheek before taking her home.
They had a relaxing evening and Kate taught Grace some math. Grace knew how to read English and Spanish, and America was helping with that. Kate was always better with numbers. Grace knew numbers up to thirty and some addition, which Kate was helping her with.
After she put Grace to bed, Kate waited up with a quiet television and a book that she couldn’t even read because it was in Spanish. Still, she made a good attempt at seeming like she was reading it.
Eventually, America opened the window and fell in. She was bruised, but unbloodied, and grinning widely. “They trapped us in an alternate timeline,” she said. “Took forever to kick my way back. You have no idea how gorgeous you look.”
Kate held back her pleasure and sniffed. “You look like a pile of dung. Don’t get within twenty feet of me until you shower.”
"If you say so, Princess." America still swaggered over and kissed Kate, who managed to contain most of her enthusiasm. Only her genuine pleasure at seeing America alive went into the kiss. They broke apart, and America’s voice was a lot lower and sexier. "One of these days we’re gonna find a babysitter for that kid. And me and you, Katie, we’re gonna have a day for ourselves."
"Oh," Kate whimpered when America kissed her again and left abruptly, heading towards the shower.
A few days (and one memorable instance of amazing sex) later, Tony showed up long enough to inform them that Grace was, indeed, their daughter, then said that they needed Hawkeye. Kate hesitated, but America bumped her shoulder. “I’m fine,” America insisted. “Just let me hang around your nice apartment for a while, I’ll take care of the kid, and you’ll get back when you get back.”
Kate looked good in her Hawkeye uniform, especially since it showed off her arms. Grace asked, “Where’s mama going?”
"She’s going out to save the day," America said, picking Grace up and flying backwards to the couch. "So we might wanna stay here for a while. Maybe when she comes back we can all go out for some ice cream or something, if it isn’t too late."
Grace smiled. “Okay.” She laid down and put her head in America’s lap, squirming until she could see the TV as America put on some cartoons.
Eventually America asked, “Why don’t you call me mama? You call Kate mama all the time.”
"Because she’s mama," Grace said simply. "You’re mama America."
America smiled. “Okay, then. Why don’t you call me mom, mija?”
"Okay," Grace said again.
When Kate finally stumbled in from fighting R.A.I.D. and the weird cyborgs they’d just invented, she found America and Grace still on the sofa, both fast asleep. Grace was using her mother’s legs as a pillow, while America was using her arm. She picked up Grace and carried her to bed. She roused America with a kiss, and America kissed back happily even though it was tempered by her tiredness. One sneaky hand went to Kate’s breast and she knocked it off. “Bed,” she said. “Now. I need to take a shower and then I’ll be in.”
By the time Kate was done with her shower and in her pajamas, America was asleep again, this time with Grace snuggling close to her side. Kate smiled and got in bed, too.