A/N: This is a deaging fic. Simple as that. I'm happy with it. At the moment it's complete, but I haven't quite decided if I'm writing a follow up or not. Time will tell. Sorry about the false warnings for those of you who got alerts, I'm hoping the problem is fixed this time..

Disclaimer: I do not own Supernatural or any of the characters, and I'm not making any money on any of this.

Backwards

The process takes months. And that, in itself, is their initial problem. By the time they know something is wrong, the witch has been ganked for almost four months, and there's nothing left to do but ride the whole thing out.

The first things to go are the crow's feet. Not all of them at once, because Dean has had them since he was sixteen. They're his smile, but.. They smooth out a little. Just a little bit.
The lines around his mouth soften as well, like the little ridges that would one day turn into wrinkles have been filled out. Still there when he smiles, but not as easy to spot when he isn't.

And then the bad back calms down a little. The hard motel beds don't leave him creaking upright in the morning, and it doesn't seem to take a long, hot shower and a big cup of coffee to put him in a state to face the day.
Dean really doesn't mind.

There are other changes. He can go for longer without stopping for rest, and his knees aren't aching with dull pain after running up a flight of stairs. His voice loses the whiskey quality it's been working for the last few years. His body, never flabby in the slightest, is leaner. Thinner. And oh hell is he hungry. He wants all kinds of things, and even the oldest, ugliest women in the diners are enough to set his mind and.. Other things racing.

It sneaks up on them, through months of hard work during the winter, pale skin made paler from the lack of sun up north, feet almost always soaked to the bone through boots and thick socks. Really, Sam doesn't have the time to catalogue his brother's body.

But finally, finally, they realise something's up.

"Can I see some ID?"

Dean hasn't been asked for ID since he was seventeen. For the first time in a long time Sam looks at his brother. Really looks. What he finds startles him. Dean's hair, always dark blonde and straight, is a bit longer than normal, and it's curling up at the ends. His lips are fuller, his face less lined. Less weary and weatherbeaten. He's smaller than Sam remembers, like his shoulders aren't as broad. His bowed legs are swimming in jeans that normally fit just fine.

"I can't accept this ID. It says here you're.. 29?"

Dean's face flushes bright red in anger. "I am friggin' 29! Says right there!"
Sam cuts him off. "No problem, miss. He'll have a coke."
His mind is dizzy with the possibilities. He recounts every witch they've ganked, every supernatural situation they've faced lately. Starts thinking, counting how long it's been since his brother started changing.
It doesn't take him long to come up with the only thought that hits him, and he's not grateful for it. He's an awful brother. His older brother just entered his teens going backwards, and Sam hasn't noticed a thing.

He flashes the waitress a faint grin, and she scowls, giving the ID back and stomping off towards the bar with Dean's insults raining over her.

"Dean" He whispers. "Dean, she's right. There's something wrong."

Dean doesn't meet his eyes.

A pause.

"How long have you known?"
"Figured it out about a month back.. Scars kept disappearin'. 's a witch. It'll wear off in like.. A year."
"A year!".
"Yeah. That's what Bobby says. Listen, I think I'm like.. 17 or 18 now. So if I've lost 11 years in 4 months it's just going to get worse, Sam. And.. We ganked her. Y'know? We can't stop this."

Sam blows out a breath in frustration, taps his feet nervously against the rubber floor of the diner.

"Yeah. I know. We'll ride it out. It's not.. Lethal, is it?"

"Wouldn't I have let you know if it was?" Dean snaps in his too smooth, too light voice, and Sam grunts. His brother knew, Bobby knew, and Sam didn't. He sleeps in the next bed. They share tiny bathrooms, and their office is a car. And he didn't know.

They keep going, hunting. Ghosts, ghouls, poltergeists. Nothing big, because Dean.. Dean barely looks old enough to drive. His clothes are hanging off him, boots dragging as he walks. He refuses to let Sam comment on it, like he's scared Sam will take off, and insists on driving wherever they go until they're pulled over one day.

"Hey there, son. Out for a test drive with your brother, huh?"
Dean growls, but Sam nods and smiles.
"Listen, officer.. We forgot the permit at home. Think you can let us off the hook this once? I'll take over the driving now, of course."

Five minutes later they leave the police car in the rear view mirror, Sam behind the wheel and Dean grumbling in the passenger seat, breaking his own rules and rifling through the white cardboard box of tapes. His face has the look of someone trying to act natural, but his eyes don't even stray towards Sam. Keep firmly to the left, even when he's putting in the tape and turning up the volume.

No talking, then. Sam is pretty sure he sees Dean thumping his head softly against the passenger window in frustration.

Sam keeps driving until they hit a wall mart, where he proceeds to stock up on simple clothes for kids. Sweats, a couple pairs of jeans, underwear, t-shirts in various sizes. Dean grunts, refuses to talk to him when he asks for approval. Sam thinks to himself that Dean is playing his part perfectly, surly teenager out shopping with his... His brother. Dammit. Awkward. The horrible situation they're in hits him like a ton of bricks, because his brother is young enough that while his head is in place, the rest of the world expects him to need a guardian. A parental figure, and fuck if Sam wants to fill that role. His stomach pools with dread now, pity for Dean, but for the most part for himself.

Then he turns the car towards California. "Time for a summer holiday, I think" he grins at his big.. Little brother, who looks about thirteen with full lips and puppy dog eyes, hair longer now and still curling at the ends. He's narrow and tiny in the passenger seat, hands soft and smooth and pale with a dusting of freckles across the knuckles. HIs voice is breaking, and his nose is too big on his face.

It goes downhill from there.

Dean isn't old enough to go out on his own, pretty soon. He can't drink anything with alcohol, because Sam wont let him, and girls think he's cute in a "Does he need a babysitter" kind of way, and he just had to give up the clothes that say '10 years' on the label.
He's officially not even a preteen. His voice is smooth, silky like a little boy, and his body.. It's pudgy. Like a little boy. Soft, pale.
There are other things going on, too. Sam goes to shower one day, and comes out to find his brother watching cartoons. Oblivious to the fact that Sam watches him for two minutes he drinks the milk from the bowl he had cereal in, and then jumps down from the bed to wash it out in the sink. His eyes never leave the screen, like he's completely enraptured by the cartoon flashing over it.

And soon enough he has to stand on his toes to reach the sink, has to climb into the car on his knees before he settles on his butt and lets Sam buckle him in, has to remember to not go places on his own, because he's barely six years old and far too little. His arms are too short and clumsy, and when he brushes his teeth or tries to eat with cutlery they're unmanageable and uncoordinated.

He's sleepy and grumpy in the afternoons, and falls asleep shortly after dinner. Sam is left in a dingy motel room without anyone keeping him company but his laptop, watching over a little boy in a blue pair of PJ's sleeping on a gigantic bed. His throat is full, suddenly. He misses Dean fiercely. His Dean.
When Dean wakes up his PJ's are almost always a little bit bigger than they were the night before.
Sam folds them away, puts them in the rapidly filling bag in the trunk. Doesn't say a word.

One morning he catches his brother brushing his teeth under the bathtub faucet.

The day Sam brings home a car seat is the day Dean throws his first tantrum. And really, he feels like he held out for a long, long time. Sam sets it up in front, which isn't right, but Dean doesn't say a word about it. His breath is still hitching, face still red and nose still clogged from a violent burst of anger, which brought on tears when Sam comes over, pick him up and settles him on one hip, duffle bag on the other.
"Come on, Dean. We've got to go now. We'll be at Bobby's tomorrow."

His breath catches as Sam settles him against his chest and takes a step towards the car, and then suddenly Sam's hand is warm against his back, comforting and rubbing just a little bit, and he leans his head against a broad shoulder. He wants to be shocked at his own behaviour, but really, he's tired and his head aches and his chest wont stop hitching with every breath, and Sam's there. Warm, solid and there.
So it takes a few extra minutes before Sam settles him in the new seat. It smells of plastic, and there's a strange contraption fastening between his legs and around his upper body like he's going to fly a fighter jet when all he's doing is sitting in a car. All he can really do is lean back or strain his head upwards, and the only movable things are his arms and his legs. The rest of him is strapped in tight, and he wriggles uncomfortably.
"Don't like it, Sammy" he mumbles, and Sam smiles.
"I know you don't, but it's there to stay for a while, all right? So just.. I dunno. What do four year olds do in the car? Want me to put on a kiddie cassette?"
He scowls up at Sam, then leans his head away from him so he can look out the window. He's uncomfortably aware of his feet, clad in velcro sneakers, dangling limply underneath him, and his hands hanging in his lap, but his eyes grow heavy not even minutes after they take off. The rumbling of the engine is soothing, the sound of home, and before he knows it he's napping.

Fucking napping.

Sam drives in the quiet for a while. It feels like forever while he watches the little blond boy sleeping quietly in his little car seat next to him. Then Dean stirs, about an hour in, and he looks down to find sleepy green eyes watching him.
"Sam?" it whispers, his voice a helium impersonation of his real self.
"Sam? I gatta go."
"Go.. Oh.Oh." Sam says, looks around blindly for a bathroom like one will materialise out of thin air. Really, this is one of the things he's been dreading.
"Can you hold it?"

But Dean is shifting uncomfortably in his seat, the straps pulling him back to the padded backrest.

"Sammy..." he says, and Sam pulls over onto the shoulder in a squeal of tires. He opens the door for his tiny brother, opens the buckles when tiny fingers aren't strong enough. Turns his back as Dean pulls down the blue sweatpants he's got one and pees all over gravel and dandelions.

When he turns again, Dean is standing there with his hands held awkwardly in front of him.

Sam stares.

Then goes to find the package of wet wipes he put in the back months ago, and hopes one of them will still be wet.
He ends up rewetting it with a bottle of carbonated water from the trunk.

Dean doesn't fall asleep again. He's chatting animatedly, arms and legs joining in on the conversation. His body is softening even while Sam watches, cheeks filling out and legs getting pudgier. He's got a lisp, and Sam is pretty sure it's the cutest thing he's ever heard.

"...'n den I just took her out, Sammy"
"Uh huh. All alone?"
"Yeah, Sammy! All 'lone!"

He can't help but laugh, because despite knowing that his badass brother is right next to him, sometimes he'd swear he was talking to a real four year old. Mostly because the witch Dean is bragging about? He's pretty sure he was the one to off her.

"..d'ya think I'll ever grow up 'gain, Sammy?"

"You will" he says, and his voice is firm and strong. Dean falls quiet again, one little finger picking at the side of his nose.

By the time they reach Bobby's it's the middle of the night, and Dean has been asleep for the last four hours. Sam waits until after he's taken their bags inside to fetch Dean, because he doesn't want to wake him up.
It's a strange sensation, being the adult who's got a kid on his hip crossing the courtyard at Bobby's in the middle of the night. The impala is behind him, fleece blanket thrown haphazardly over the car seat up front, and if it wasn't for the grey hairs on Bobby's head it would be like the last 26 years never happened. The Winchesters arrive in the dead of night, kids sleeping in the car and the adults rubbing tired eyes with a grungy fist. Dean's got a thumb lodged safely in his mouth, his head heavy and warm on Sam's shoulder as he walks inside.

"Damn." Bobby says, but that's all he can seemingly think of to say. Sam nods, then walks them both up the stairs and settle the tiny version of his brother on the bed next to his in their old guest room. He watches for a moment, frowns down at the tiny thing, and starts undressing him carefully. With soft hands and quiet shushing he's soon enough got the kid out of all of his clothes, and the thought of modesty didn't actually cross his mind until he sees his brother butt naked on the bed.

He blushes, tells himself that he's barely three years old. This is how it goes, dammit.
Sam's never had a kid before, and it's a rude introduction to the strange situations it brings.
There's a pair of onepiece pajamas in the bag he brought upstairs. They've got the tags on still, and Sam never thought he'd use them. He picked them up to make his then surly teenager of a brother throw a fit. It worked. But now? They fit like a glove, and while he watches Dean curls up on his side, lodges his thumb right back in his mouth and pulls the blanket close like a bear.

Sam swallows down that lump again, the big one, and goes to bed.

The next morning is different. Dean is sitting on his bed, blankets still around him and thumb dropping from his mouth and wiping off on his PJ's like he doesn't want Sam to see.
"Good morning" Sam croaks, but Dean just watches him. Wipes his nose with a sleeve that's too long. Whispy, blonde hair is growing on his head and his body is chubby and short, cheeks pudgy and red from sleep.

Then, without warning, he bursts out crying.

It takes Sam a while to get things calmed down. Actually, he doesn't, and by the time Dean is almost vomiting from crying for so long Bobby steps in, big hands and flannel shirt rubbing up and down Dean's back, a wet cloth wiping at a hot, tear stained face.

"Go get him something to wear. Go shopping. I don't care, I'll get this. And strip off that bed, dammit."

Sam is all too happy to escape, so with soaked sheets under one arm he practically runs downstairs and leaves Dean sobbing heartbrokenly in Bobby's arms. He goes straight to the closest mall. Escapes with a few bags worth of stuff, and arrives back home after smoking three cigarettes, drinking two large lattes in the car and crushing the muffin he bought by leaning on it while reaching for his wallet on the passenger seat.

When he comes inside he finds Dean sitting in the kitchen eating yoghurt on a chair that's attached to the table edge. The yoghurt is covering him from nose to chin, but he's smiling. Laughing as Sam comes in. Genuinely happy to see him, it seems. Childish joy bubbling up to his face and leaving a grin Sam can only barely remember, and only in an older version. Tiny hands reach up for him and he lifts the little boy up, leans him against one shoulder and frowns down at the too large clothes and the feel of damp yoghurt soaking through his shirt.

Dean protests violently at being undressed, and keeps it up as Sam puts him in the tub with a few inches of water. Whines as he pours lukewarm water over his head to rinse out shampoo, and protests desperately when Sam puts him on a towel on the floor to get him changed. Sam doesn't doubt that his mind is still there, but he doesn't know if he's relieved or not.

Sam doesn't care. They've arrived at the bottom, and he's about to figure out just how awkward it is to stick your 29 year old brother with a pacifier, a diaper and a teddy bear. And if Dean wants to kill him for it, he'll have to get potty trained first.

That night, he's got a sleepy boy resting on one arm while the other holds a bottle of warm milk that Bobby just warmed for him. The little boy is blinking heavy lidded green eyes, watching him like he hung the moon. He's wearing the tiniest little sleeper, complete with feet and little race cars, and Sam can't help but smile as the eyes fall closed only to open a second later, never breaking the rhythm of the milk going down.

He can handle this. He's pretty sure they'll be just fine.

-fin-