The first time Sam catches Dean smoking, it’s right after they snagged their first black dog. Sam’s got a pretty nasty gash on his cheek, and Dean’s got a few scratches on his forearm, but other than that, they’re fine. Just part of the job. And when Sam sees that cancer stick poking out of Dean’s mouth, smoke curling out from Dean’s nose and lips, Sam wants to run over and yank it away, stomp on it until it was unrecognizable, because how could Dean be allowing that acrid…stuff fill his lungs? It kills so many people, including their great aunt Gene, but Sam had never met her, so he guessed that she wasn’t a very good example. But. Smoking? Sam thought that Dean had better sense than that. They both had to sit through that health class back in Louisiana, didn’t Dean remember that blackened pig’s lung they had brought in for the health fair? But Sam did nothing, hid in the shadows until Dean crushed the butt against the curb he was sitting on and flicked it out into the motel parking lot before heading back inside. He followed a few minutes afterwards, still trying to wrap his brain around it. Stupid Dean and his stupid need to be cool​, Sam grumbled to himself glumly.

Dean was lying on their bed, head propped against his pillow while he watched some movie with enough of a body count to keep him semi-interested. Sam plopped down at the table to do his homework while trying to devise a way of stealing the rest of the pack Dean had to have without getting caught. When Sam was just finishing up, Dean switched off the TV and went over to give Sam a quick kiss before his shower. Dean tasted like smoke, and Sam wanted to hurl from the intensity of it. Dean pulled away, pecked Sam one last time, and wandered over to the bathroom door. Sam sat still for a few minutes, trying to keep his stomach from turning inside out at the residual taste left on his tongue before getting up to search for the pack of cigarettes. He found it buried at the bottom of Dean’s ​duffle​, and crumpled it in his hand when he saw that more than half the pack was already gone. He charged outside and hurled it into the dumpster, his chest heaving in frustration. Damn if Dean found out; he’d better not stick another one in his mouth or God help him Sam was going to punch Dean straight in the face and grind that cigarette into the sleeve of Dean’s favorite leather jacket. That’d teach him not to suck down cancer sticks like it didn’t even matter.

Sam quietly walked back into the motel room, packed​ up his now finished homework and flopped onto his dad’s bed, trying to calm his breathing to a level where Dean wouldn’t notice. Dean breezed back into the room in nothing but a towel, all but whistling from his post-hunt high that Sam never understood but knew was inherently Dean​.​ He bent down to rifle through his duffle and Sam didn’t even care if Dean noticed his cigarettes were gone because Fuck​.​ Him.

Sam could tell the exact moment Dean noticed their absence by the muscles in Dean’s back tensing all at once.

“Sammy?” Dean questioned quietly, his voice laced​ with danger and barely concealed anger. Sam didn’t even fucking care.

“What Dean?” Sam asked, confrontation clear in his voice.

“You know damn well what!” Dean yelled, whirling around to see an equally enraged Sammy. “Where. Are. They?”

“Fuck you, Dean! Don’t you know anything​? Those things will kill you!” Sam clenched his fists at his sides, trying to keep himself from actually attacking his older, fucking idiotic brother. God, Dean was so stupid sometimes.

“Fuck you, Sam! Give ‘em back!” Dean was visibly shaking, barely controlling his rage.

“Dean, c’mon! Your teeth are gonna turn yellow and fall out, your hair and clothes will smell bad, you’re gonna get a bunch of diseases, and you won’t be able to taste anything! Why the FUCK would you willingly suck one of those things into your lungs!?” Sam screamed. He was pissed. Well and truly pissed. If Dean didn’t back down, Sam wasn’t sure what he was going to do, but he knew it wouldn’t be good.

“Because it helps me CALM DOWN!” Dean bellowed and slapped Sam across the face. He didn’t plan on doing it; it just happened. Sam recoiled from the hit, holding his hand against his burning cheek in shock. No matter how bad they fought, Dean had never hit Sam before, not even when Dean came back one night to find Sam cutting holes in his favorite Metallica t-shirt because Sam couldn’t find any paper to make “snowflakes for daddy”. That was when Sam was 3.

“Fine.” Sam said quietly, turning away. “You’ll find your cigarettes in the dumpster.” And with that, Sam stormed out of the room, eyes filled with angry tears.

“Fuck,” Dean said eloquently and slumped down on his and Sam’s bed. He really fucked up this time.