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Reasonable to Assume

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It's kind of weird, having the house all to himself. Dad's away attending that compulsory four-week anti-terrorism seminar in Los Angeles, which is bizarre, since what are the odds of terrorists attacking Beacon Hills? An anti-werewolf training camp would be way more useful. Not that Stiles is particularly anti-werewolf. These days.

Anyway, it's weird, and maybe a little lonely - not that Stiles will ever admit it, especially not to Dad, who might decide to dole out one of his irresistible but nonetheless emasculating hugs. Stiles makes up for it by spending his summer holidays pretty much hanging out at Scott's and playing video games, or hanging out at Danny's and playing video games, or hanging out in the forest and playing… tag. If that's what you can call it, given that Jackson's the Omega and is therefore always 'it'. It's sort of pathetic to watch, but mostly, it's hilarious. Deeply, deeply hilarious. Stiles still isn't sure how the whole ranking thing works out, but somehow, both Scott and Lydia are Betas, and Jackson's at the bottom of the pecking order. Stiles can't get enough of it.

Derek's still… Derek, except that he's even broodier and pissier than before. He can be pseudo-gentle, though, especially when it comes to his pack; he only brutalizes them about two-thirds of the time, and the rest of the time, he just sits back and watches them with an almost-fond expression on his face. Maybe. Or possibly, Stiles is hallucinating. The forest probably has psychotropic qualities. It'd explain a lot. Especially about Scott, unless those are just Allison's pheromones he's high on.

So, all in all, it's a weird but not-too-bad summer, until his phone vibrates at 7 a.m. one morning. In the morning, what the fuck is up with that?

Stiles feels the phone vibrating under his back - he's gotta stop sleeping with the thing - and scrambles for it sleepily, fumbling with its skin-warmed surface until he finds the right button.

"…'llo?" he croaks.

"Stiles," says Derek, which isn't unusual, except that what he says next totally is. "Bring diapers."


But Derek's hung up, and Stiles is left staring at the phone, wondering if the forest really is psychotropic, after all.



Stiles brings diapers.

He also buys baby powder from the local drugstore, not to mention Johnson's baby shampoo, moisturizer, milk powder and a rubber duck. Just 'cause. There's also a couple milk bottles from the time Aunt Judy stayed over with her twins, which he shoves into a plastic bag with vague ideas about boiling them as soon as he gets to the Hale house. Sanitization, he remembers, is important. And if he's also printed out all 204 pages of an ebook called How to Take Care of Your Baby by Imogen Marsters on Dad's laser printer, well, that doesn't make him any less of a man.

At first, he'd wondered if Derek had suddenly aged and required continence diapers, but when he'd called Derek back to explain his brilliant theory, Derek had just growled, and yeah, that was a baby crying in the background.

A baby.

Derek had a baby.

Derek. Had. A baby.

Once Stiles's brain had stopped frying in its own juices (it didn't take too long; by now, he was used to insanity), he'd promptly changed into his jeans, brushed his teeth and composed a mental list of Things That Babies Absolutely Must Have. Then he'd looked up the Marsters ebook, printed it, and rushed off with his wallet and a sizeable portion of his allowance. The lady in the drugstore had sniffed at him like he was crazy - or like he'd gotten a girl pregnant and was secretly buying supplies for her baby.

Stiles is pretty sure he hasn't gotten Derek pregnant. Given that Derek hasn't come within two feet of him since becoming an Alpha (it's been a strange experience, not getting thrown against random surfaces), not that they'd ever gotten beyond the occasional awkward moment of is-it-eye-fucking-or-isn't-it, anyway. Also, why is he even thinking of baby-making and Derek in the same sentence? Freaky.

He has no idea where the baby came from - but when he gets to Derek's place, he sure as hell is gonna find out.



Stiles almost breaks his back, getting all the bags full of baby-things in the door, but he can't even notice the agony his muscles are in, because he can hear the baby crying. Wailing, even. An ear-piercing, head-splitting wail. Jesus, it's more like a car alarm than a sound that can even be produced by a biological being. It's a good thing Derek lives out in the woods, or the arrival of the baby would attract the attention of every single neighbor within hearing distance.

He leaves the bags by the entrance and heads into the newly-renovated living room, just in time to see Derek freaking out.

Well, okay, it's Derek, so the only way to tell he's freaking out is by noticing that his eyebrows are a little higher on his face and he looks less like a wanted felon out to kill someone than he does a cornered beast out to kill someone. Derek is also standing at the opposite end of the room from the source of all the noise, as if just standing far away from the baby will make it go away.

"What are you doing?" Stiles hurries over to the basket - it's seriously a basket, Moses-style - that's sitting on the coffee table. "Have you even fed this kid?"

"I had nothing to feed it," says Derek, and, yeah, unless you count the mountains of red meat in his fridge or the bits of desiccated rabbit in the garden… uh.


The baby… the baby is furry. Really furry. And Stiles has seen a few hairy babies, mostly because the guys on Mom's side of the family are hirsute and their little tykes are, too - but this isn't hairy, it's furry. Smooth, shiny, soft and furry. It's a naked boy-baby, and his fists are clenched tight, and his tiny mouth's wide open as he cries, affording Stiles a clear view of bumpy gums. Very sharp bumpy gums. The sort that'll grow into fangs, not teeth.

It's just - it's a mini-werewolf, and it shouldn't be cute, except that it somehow is, because it's still helpless and small and the way its face is flushed red with distress just… makes Stiles want to chase all the bad things away.

Christ. Possibly he could've been more emotionally prepared for this. He hadn't realized that a werewolf baby was basically a cross between a puppy and a baby and therefore doubled the cuteness factor, but, damn. This isn't just a baby, it's a weapon of mass destruction. No one, not even Peter Hale, could survive this level of cuteness. It's making pink clouds of… of pinkness explode inside his brain.

"So," says Stiles, when he gathers what's left of his wits, "he yours?"

"What?" Derek barks the question.

"Uh, you know, is there some she-wolf you mated with out in the woods? Did she just drop him off? For the weekend, or whatever?"

"He is not mine," Derek growls, and the baby wails louder.

"Don't make that sound! It scares him!"

"Too bad. It's the first sound he heard me make."

"And now, he won't let you near him without crying." Then, Stiles realizes something. "You growled at a baby?"

Derek looks uncomfortable, and it's so wrong seeing that expression on an Alpha's face that Stiles goggles. "I… was not growling at him."

"Then who were you growling at?"

Derek rolls his shoulders - his very, very huge shoulders, that seem to have gotten even huger since he became the Alpha. "I don't know. I woke to an unfamiliar scent near the house, and ran out to check who it was. It smelled like a female werewolf - a female unknown to me." He's glaring at Stiles, again. Why is he glaring at Stiles? Isn't it a perfectly reasonable assumption to make, that a dude with a surprise baby might actually have fathered said baby? On someone?

"Right," says Stiles. "So - you were chasing an intruder. Growling while chasing an intruder. And then what?"

"I found this on the doorstep." Derek's voice sharpens when he says 'this', like it's an accusation. "I couldn't keep chasing whoever it was."

"Why not? …Oh, wait, don't answer that. You couldn't leave a baby alone in an abandoned house in the middle of a forest with potential predators in it. Fine. So the kid heard you growling, the first time he met you, and now he thinks you're a bad man." Stiles can't help the smile pulling at the corners of his mouth. "How's that feel? Being villanized by an infant?"

"Shut up," says Derek, somehow managing not to growl - even though he wants to, it's totally obvious from his eyebrows. "And do something."

"Do something?" Stiles is out-and-out grinning. "About what?"

"About that."

The baby's still crying. A lot lower, now that Derek isn't being the Big Bad Wolf, and Stiles is drawn to the kid's side like a magnet.

"Hey, little guy," he says, softly, and meets the baby's eyes. They blink at him, iridescent-green and wet, the baby temporarily distracted from his crying by the sight of a new face. "The mean wolf spooked you, didn't he? Don't worry. I won't let him hurt you."

"What are you saying?" Derek hisses. "I would never hurt a - "

"Be quiet, Derek," says Stiles, sweetly, still smiling down at the kid. "You're hungry, aren't you? There's some milk on the way."

"Milk," mutters Derek, off to the side. "I forgot to ask you to buy milk."

"I bought it, anyway." Still out of the corner of his mouth, he tells Derek: "Go get the bags by the door, would you? Take the powder out, mix it with water and boil it on the stove. Boil one of the bottles, too. Separately. Then put the milk in the bottle and bring it here, okay? We'll have to wait for it to cool before he can drink from it."

Derek just stands there. What, does he think he's too Alpha to boil a baby's milk? Tough luck.

"Do you want him to starve to death, or what?"

Derek goes.

Stiles hears the rustling of plastic bags in the corridor, and he reaches down to touch the baby, fingers resting on his cheek, and, wow, that fur's the most velvety, most unbelievably irresistible thing ever. He looks back into the baby's eyes - as if asking for permission - and reaches under that tiny body to lift it up. The baby stops sniffling entirely, startled into silence.

"Whoa, hey, you're light. Lighter than a feather, almost. A really furry feather. Fluffy feather. God, you're fluffy. And naked. Very naked. That embarrass you? Or does the fur make up for it?"

The baby just looks at him.

"How old are you? You can't be more than, what, three months old? Four? Practically newborn. Damn, you're cute. Scary-cute. Cute-scary. I don't even know. You have a name?"

The baby's feet kick slightly.

"Lemme guess. It ain't Jarvis. Because, you and a giant suit of sentient armor? Not much in common. Except for the sentience. And, you know, the ability to level entire cities. One, with firepower; the other, with cute. You're cuuuuuuuute," he says, and hugs the baby to him.

He hopes he's holding it correctly; Aunt Judy seemed to think he had a talent for it, at least, which is a comfort. With one palm cradling the baby's head and the other under his velvet-furred bottom, he holds the baby close, and whispers to him.

"Cutest thing ever, that's what you are. Oh, yeah. Do that cooing thing. You like it when I hug you? You like being hugged? 'Course you do. It's the Stilinski hug, man, it's the best hug in the world. We, like, have the hugging gene. We're hugging mutants. Rawr. Rawwwrrrr, see? It's not scary. Not when a hug-wolf does it. Way better than a sour-wolf, right?"

"What are you saying to him?"

Oops. Derek's back, and he's holding a milk bottle like it's a club. Isn't Derek ever going to stop with the caveman routine?

"Um, just. You know. Propaganda? Perfectly harmless propaganda? That favors Stilinskis over Hales? What?"

Derek stares at him like he's insane. Hey, Stiles isn't the one that can't even cope with a baby.

Stiles sighs, sits down on the couch, and settles the baby on his lap. "Gimme that bottle."

Derek gives him the bottle. And immediately steps back, like there's a defense perimeter around the baby that he can't breach, probably because it's lined with mines.

It's Stiles's turn to stare. "Are you frightened of the baby?"

"No," says Derek, too quickly. "I just - don't know what to do with him."

"You're a werewolf! He's a werebaby! How can you not know what to do with him?"

"I was the youngest in my family," says Derek, defensively. "I have no experience with cubs."

"Cu - cubs. Uh-huh. Which, all right, he is a cub, but, seriously?" Stiles isn't going to snicker. He isn't. "So what you're telling me is that you can't handle a baby because you used to be the baby. Of your family."

Derek's brows lower.

"Don't growl! I can see your eyes doing that Red October thing, but it isn't the best idea right now, okay? The kid's just stopped crying."

Derek pauses, like someone literally pressed the pause-button, and nods. His eyes clear.

Stiles wonders just how painful those high-pitched cries must be for fully-grown, highly sensitive werewolf ears. Derek doesn't usually cooperate like this. With anything Stiles suggests, let alone - well, anything.

Or maybe Derek's just desperate. The thought's honestly funny - that Derek Hale, Alpha of Beacon Hills, overly muscular ex-convict and badass, parricidal mofo, is desperate for a babysitter.

Stiles laughs.

Derek clenches his jaw.

"Look, I'm sorry, just - heh. Can you blame me? Also, have you told Scott? About our li'l guest?"

"I sent him a message soon after I sent you one."


"He didn't show up. He must've thought it was a joke."

Stiles… blinks. "He still thinks you're capable of a sense of humor?"

Derek scowls.

"Hey, chill. I hate to say this about my best friend, but… he isn't the brightest wolf in the pack." That word, 'pack', reminds him of a question that's been niggling at him. "Why'd you even ask me, first? Why not Lydia?" No one in their right minds would ask Jackson, but Lydia had to be the likeliest candidate, didn't she?

Derek's scowl deepens. "Why would I ask her?"

"Uh. Because she's… one of your Betas? And, yeah, she's a single child, but she's a girl, so that's gotta give her some innate talent for soothing babies."

"You share Scott's lack of understanding about your pack."

"My - my pack?"

But Derek goes rigid, from head to toe, like he's said something he shouldn't have. The scowl's replaced by that cornered look.

Stiles gapes, fascinated. The baby gurgles in his lap. "Um," says Stiles. "That - I didn't know that. That you thought - that."

"Forget about it. Feed the baby."

Forget about it? Derek, the Alpha, thinks Stiles is a member of his pack, and Stiles is supposed to forget about it? "The bottle's not cool enough."

Derek narrows his eyes.

Stiles narrows his right back.

Finally, astonishingly, Derek looks away. It's a surrender of such epic proportions - for a werewolf - that Stiles can barely process it. "It isn't a big deal," Derek says. "You must remember how I told you and Scott that my family once consisted of both humans and werewolves."

"Yeah. Yeah, you did, come to think of it."

"That's all it is."

"That's - " But that's not all it is. Stiles doesn't know how, but he can feel it, in the way Derek's shoulders are tense, in the way the silence that falls between them is tense.

Usually, Stiles would just badger Derek into telling him what was up, but Derek's weirdly edgy, like he might jump out of a window, or something. It's downright bizarre.

So Stiles files this away in his mind, in the file titled, 'Things To Talk About With Derek Hale in the Unlikely Event That He is Sane, Drugged Into Complacency or is Otherwise Restrained and is Unable to Maul Me'. His Derek-files tend to have long names. Derek's that kind of guy. "Fine," says Stiles, like he means it, and Derek can always tell when he's lying, but Derek - again, astonishingly - doesn't comment on it.

"Is the milk cool enough, yet?"

Wow, what a smooth subject change. Not. "Yep, I think it is."

Stiles uncaps the bottle, and the smell of milk intensifies. The baby must be able to smell it, too - better than Stiles can - because his furry hands make vague grabbing motions, eyes fixed on the bottle like heat-seeking missiles on a soon-to-be-blasted-into-smithereens target. His irises even glow green. "Would you look at that. Just like Daddy."

"I'm not his father - "

"Didn't say you were." Stiles quirks a grin at Derek, and plugs the rubber nipple into the baby's mouth. The kid does this full-body freeze, toes pointing straight out, before he starts sucking frantically.

It's the most adorable thing Stiles has ever seen. His heart literally thumps in his chest. And maybe the baby hears it, because he snuggles closer, and gazes up at Stiles with a pleased, deeply satisfied face. His mouth keeps on sucking, though, like it's on autopilot.

"Hey, kiddo. You were hungry, huh? You've been a sweetheart, really, even though Derek's, like, the worst host."


"Stop trying to defend yourself to an infant, dude. It's pathetic."

"Stop trying to make me look bad in front of one. That's pathetic, too."

Stiles sticks out his tongue. At Derek, but the kid probably finds it amusing, because he makes this fart-noise around his bottle.

"At least you can laugh. Sourwolf, here? Wouldn't know comedy if the entire cast of Monty Python took up residence inside his head."

"I don't own a television."

"See? Clearly, a deficient being. With many deficiencies."


"What?" Stiles glances up at Derek - and he totally expects Derek to be glowering, except… he's not. He's got that look on his face - that look he gets when he watches Lydia and Scott and Jackson playing wolf-tag in the woods.

It's… Stiles doesn't know what that look is. But Derek's giving it to him, has it because of him, and that's -

Stiles doesn't know what that means, either. Except that it makes his throat go dry.

"You're good with cubs," Derek says, out of the blue, and Stiles starts. The baby's fist comes up to clutch Stiles's shirt, as if to keep him still.

"Uh. You could write me a letter of recommendation? If I ever decide to become a professional au pair?"

Derek snorts. "It would suit you."

"I was joking. I - ohmygod, you just made a joke, too. You made a joke. You made a joke. Where is my camera. Where is any camera. This moment needs to be recorded for posterity. It needs to be recorded for your cubs, man."

"My cubs," says Derek, and stills. All over.

"Um. Yeah? You need some, right? Eventually? To build your pack?"

"Scott and Jackson both have mates. They can produce cubs."

"What about you? Doesn't the Alpha have to produce any cubs? Although, what is up with that word? 'Produce,' like it's a factory line, or - "

"Will you look after them?"


"My cubs," Derek repeats, patiently, and his eyes are strangely intent. They're red, again, but it isn't the angry red. It's… something else. Something that goes along with that other expression Derek had been wearing. "Will you look after them, the way you're looking after this cub?"


What even -

"Well, yeah," says Stiles, even though he gets the feeling that he isn't, actually, answering the question. And he has no idea why. "I mean, I - if I'm still in Beacon Hills when that happens, sure. Why not?"

"Why not," echoes Derek, and his eyes are seriously starting to bore holes into Stiles's skull.

This time, it's Stiles that has to look away. At the baby, because the baby's safe, because the baby's tiny, because the baby needs him now, and not X number of years in the future, to fulfill some ludicrous promise about potential offspring. What?

He isn't thinking about it. He isn't.

"Yo, Jar," he says to the baby, instead, tilting the rapidly-emptying bottle. "When you're done feeding, we'll give you a little bath, and then we'll put you in diapers, how's that sound? It sounds awesome, I know, because who wants to poop all over themselves? Not a sophisticated dude like you, I bet. Ain't that right? You know it's right. Mm-hm. Drink that milk."

Derek is… still looking at him. Stiles can sense it. "What is 'Jar'?"

"His name," says Stiles, not returning Derek's creepy stalker-scrutiny. "I can't keep calling him 'little guy' and 'mini-wolf' and 'tiny tot', can I? That sort of thing'll give him a complex. For life. Possibly a size complex. Which is the cruelest thing you can do to a guy, you know that."

"Jar." Derek tries it out. "What does it stand for?"


"Jarvis." And Derek's back to sounding like Stiles is insane. It's enough of a relief that Stiles manages to return his gaze. Derek looks - there is no other word for it - incredulous. His eyebrows don't even seem to know what to do.

Stiles beams at him. "Isn't it the coolest name in history? It's the name of Iron Man's armor! Smartest piece of military technology in the fictional future. According to the House of M, anyway."

"I have no idea what you're talking about."

"It's a comic book, Derek. Ever read those? They're like books, except with comics in them?"

"You named a cub… after a comic book."

"After a character in a comic book. An artificially intelligent character with, like, a nuclear arsenal up its sleeve. Its very shiny, metallic sleeve. Uh. What's wrong?"

But Derek's busy acting like Peter Hale had acted when both Scott's username and password had turned out to be 'Allison'.

How unfair is it that this is when Stiles finally gets the family resemblance? "Dude, you're a mythology nerd. A mythology nerd. You don't have the right to look down on a geek, okay? Because, geeks? Trump nerds. Any day."

"My thorough knowledge of Celtic mythology is a must - "

"Yeah. That explains why, along with the wolfsbane stuff, you also have stuff on love potions. And fertility potions."

"You - who showed you my library?"

"It may have been Jackson," says Stiles, which is totally a lie, it was Scott, but maybe this can get Jackson kicked around some more.

Sadly, Derek sees - or smells - through his lie. Like always. "I will kill Scott," he says, with absolute, menacing certainty, and Stiles gulps. Jar actually flinches a little, in his lap. And stops sucking.

"You've scared him again!"

"You goaded me into scaring him."

"That doesn't even make any sense. Either calm the hell down, or leave the room. Jar has to feed."

They glare at each other.

Jar burps. And resumes sucking.

They keep glaring at each other.

"You do realize," Derek grits out, "that I'm the Alpha."

"And that you could break my scrawny little neck like a twig? Yeah. Now, could you please leave the room if death threats are the only things you can produce in the presence of infants?"

"I wasn't - " Derek blinks, and his eyes are back to a shocked, human blue. "I wasn't threatening you."

"You sure weren't. 'Cause who else will take care of the cubs? Cub," he quickly corrects, when Derek's eyes widen. "This cub. This cub, specifically. Jarvis, named after the best automail ever, and that includes Fullmetal Alchemist. Damn, I've gotta catch up on my summer anime. What? What're you gawking at?"

"I," says Derek. "That. Is there. What should I do with the other bottles."

"Boil them, too. Oh, and draw a bath. He's gonna need one."

"Good," says Derek, still looking like he's been hit over the head. "That's - good."

Stiles watches him go. And wonders what the hell gets into Derek, sometimes.

"We'll try to find your Mommy and Daddy," says Stiles to Jar, in a confidential tone, "but if you do stay here, be warned - stepdaddy is one weird son of a - b-word that I cannot use in front of a baby. Yeah."

Jar stretches contentedly. And keeps on feeding.