Disclaimer: I don't own a single Winchester and never will.

Characters: Sam and Dean Winchester

Setting: Pre-Pilot all the way through to the last episode of the fifth season

Warning(s): Um…kind of sad? A little? At parts?

Can't Break a Pinky Promise

The first time Dean Winchester ever made a promise, he was five years old, standing in his front yard watching his home burn. He'd been a child then, and like all children he didn't really understand the gravity of his promise. He didn't even really understand that the fire was quickly swallowing all of his stuff—his room, his tee-ball equipment, his comic books, and everything else. He was too young to understand all the ways that his life had changed the moment he'd crossed the threshold with his brother in his arms. He didn't realize that he was going to spend the next twenty-some years of his life being mother, father, and best friend to that brother.

He certainly didn't know how those twenty-some years were going to end.

He really only knew one thing—Sammy was crying, was screaming as if the world would end, and it was up to Dean to calm him down.

"It's gonna be okay, Sammy," he repeated, joggling the blanket-wrapped bundle in his arms. "I promise."

Sam began to quiet at the sound of his voice, setting a precedent for the hard years to come. Dean repeated it more firmly. "I promise."

XXX

Dean did not make Sam a promise for another six years. He never needed to—since he was big enough to lisp out the word "brother" while pointing a chubby little finger at Dean, he'd always seemed to take for granted that anything Dean said, whether in the form of a promise or not, was to be believed without question.

Until now, apparently.

Dean sighed in exasperation as Sam's lower lip jutted out at him—Sam's pouting never led to anything good.

"Sammy, you have to go to school."

"I don't want to."

"Well, neither do I, but I have to!"

Sam's lip stuck out even further. "I'm not going. What if you guys forget to pick me up?"

"…What?" Dean asked blankly. "Sammy, why would you think we'd forget you?"

"Because Eric told me that his dad never remembers to pick him up, and he has to wait outside alone forever for the teacher to come out and the teacher always gets real mad, and Eric hates it. I don't want that to happen to me, Dean."

Sam stared up at him, so serious, so absolutely terrified at the idea of being left alone, that Dean didn't feel even slightly tempted to laugh. He honestly didn't have any idea what to do. He could not, in good conscience, simply drag Sam off to school without even attempting to alleviate his fears. He could go get his dad, but he'd never done that before and he didn't want to now. But he just wasn't prepared for this—Sam had always been so ready to trust him before.

But then he had a flash of inspiration as, all at once, the image of something he'd seen kids at school doing popped into his mind.

Without another thought he crouched down so that he was eye-level with Sam.

"Sammy, listen to me. I'm going to be there to pick you up today." His school let out earlier than Sam's kindergarten class, so he felt safe guaranteeing that. "I pinky promise, okay?"

"What's that mean?"

"Well, here, give me your hand."

Looking dubious, as though sure this couldn't possibly work, Sam held out his little hand. Dean took it and linked their pinkies together, shaking both their hands up and down.

"That's a pinky promise, Sammy, and you can't break a pinky promise. So I'm pinky promising that I'll never, ever forget you, okay?"

And Sam believed him, thus setting another precedent.

XXX

When Dean was eleven, he had his first surgery. He didn't know it would be the first of many, and so of course he was scared, though of course he took it like a man and didn't speak his fears aloud.

But he wasn't half so frightened as Sam seemed to be.

"Seriously, Sammy, it's just tonsillitis. People get it all the time. No big deal," Dean said, repeating virtually word-for-word what everyone from the doctor to his dad had told him after his diagnosis.

"But what if something happens?" Sam whispered, looking as worried as if he were the one with a surgery slotted for an hour. "What if you don't come out?"

Really, the kid knew too much about hospitals for his own good, even back then.

"I'll come out, Sammy. Hey," he added, when Sam looked skeptical. "C'mere." Sam moved cautiously closer, and Dean held out his hand.

They didn't do this often, because somehow it had become an important, almost sacred, ritual, but they did it enough that Sam knew immediately where it was going. Without hesitation, he reached out and hooked Dean's pinky through his and shook it up and down, while together they intoned, "Can't break a pinky promise."

Sam smiled, and believed him.

XXX

Sam was eighteen and leaving, and Dean didn't know how they'd gotten here.

He hadn't seen it coming, though he realized now that Sam must have given all sorts of signs. But Dean had not heeded the warnings, and now they were all paying for it.

He drove Sam to the bus station two days after the kid's birthday, and for the whole ride neither of them said a word, the silence heavy with the words shouted an hour before. It was rare that any silence between them was awkward, but this one was, and Dean found himself pathetically glad to reach the station, though he should have wanted the ride to go on forever.

Sam stayed frozen in his seat once the car was stopped, staring at him, and Dean waited for the kid to instigate some huge chick-flick moment.

But Sam just said, "Thanks for the ride," and then went on staring, as if waiting for something.

"Sure," Dean said. "Uh…what time's your bus leave?"

"Nine."

"Oh. Okay. So I guess you'd better…ya know…get your ticket and stuff."

"Yeah. So…I guess this is goodbye, then."

"Yeah, I guess it is," Dean said. "So…I guess…I'll see ya, kid."

That seemed to be what Sam was waiting for, because he pounced immediately. "Promise?"

And instantly, Dean knew what his brother had been waiting for. He felt the shadow of a smile on his lips as he looked Sam in the eye and replied, "I promise."

They didn't link pinkies, didn't murmur the words of their childhood ritual, but the intention was there, and as Sam got out of the car and walked away, slightly less miserable than he might otherwise have been, Dean allowed himself the vulnerability of saying it aloud in the privacy of his car.

"Can't break a pinky promise."

He kept that promise, too.

Eventually.

XXX

Nine years later, Sam asked Dean to let him rot in Hell. His ridiculously puppyish eyes that hadn't lost their punch even after all this time stared into Dean's, and he calmly asked his big brother to lose him and let him stay lost.

Dean…couldn't believe it. He really, honestly could not comprehend it.

And he argued. Of course he argued. But honestly, he'd never really expected it to do any good. Because Sam was still Sam—a changed, stripped-down, exhausted version, Sam 2.0, but still, at the deepest level, himself: stubborn, and determined to do what he thought was right, whether it actually was or not.

Dean still argued.

Sam responded by asking him to promise.

It was in that moment, as he looked at his doomed baby brother, that realization crystallized in Dean. In a second he seemed to relieve every promise he'd kept to Sam through their entire lives, and every one he'd broken, too.

In reality, he'd known from the moment this conversation began that he would promise. Because really, right now, he was ready to grant Sam anything he wanted—even this. IT was twisted, it was crazy, it was so totally wrong to promise to let Sam die, but he did it.

He did it, and as he'd known he would, he regretted it.

He regretted it when he woke up every morning, and he regretted it when he went to sleep every night, and he regretted it all the minutes in between. He learned to live with the regret blanketing him like a second skin at all times, and every moment of every day the words repeated themselves endlessly in the back of his mind.

Can't break a pinky promise.

He and Sam hadn't actually done the childhood ritual, but like when Sam had gone to school, the intention was there, and the intention was there, and the intention was enough to bind Dean to his promise.

And he did keep that promise not to go poking at Lucifer's cage.

It was Sam who broke it, in the end.

Author's Note: Okay, so this was supposed to be a light, happy, fluffy little Wee!Chester one-shot. Not really sure how it ended up…this. Maybe it's the disaster movie marathon I was having while writing. BUT—it did what it was supposed to do. It kept me from reading Rob Thurman's new book. It helped me avoid temptation, so it's good in my book. Hope you all enjoyed it, and review, pretty please!