john didnt notice at first, and dean doesnt remember if that encouraged him to continue or not. sams pacifier had been lost in the fire, the baby scared and crying in dean’s arms as he held him while his father tried to explain what he saw to the firefighters. john had sounded like a blubbering mess of a man, sounded mad as he told them about how his wife had been pinned to the ceiling, her white night dress stained with her blood and guts. while dean craddled sam in his small arms, watched his baby brother’s face go from being wrinkled up in anguish to a soft and sweet expression of contentment at being offered dean’s own small thumb. dean had giggled, cooing at his younger brother like he’d done when tucking him in bed with mom.
itd continued after that night, john being too preoccupied, for the short time they still lived in that house, with staying up and doing rounds around the house. checking the salt lines around the doors and windows, and drawing symbols on the walls and floors to ward away whatever he could find a deterrent for.
dean doesnt remember those days well, remembers a few nights of staying up with his father while sammy slept cradled in his lap, stirring every time dean tried to take his thumb away.
by the time john realized, it was only a year or so later, muttering something about how its good he’s taking care of sam. it had made dean smile to himself, smoothing the chestnut hair.
but by the time sam was four, it wasnt as cute. john was starting to make comments about how sam wouldnt of even had a pacifier this long, furrowed eyebrows and narrowed eyes looking down at his eldest son as he told him to quit that “sissy” shit.
dean had stopped doing it where john could see, retreating to the dark shadows of the backseat of the impala, sam in the middle seat next to him with his head on dean’s shoulder. sam wouldnt be able to sleep even though he’d just been out like a light forty five minutes ago before john woke them up to leave, whispering under the loud rattle of music shaking from the speakers sam would tell dean “just till i fall asleep?”
dean would oblige, sneaking his hand around sam’s shoulders and nudging his thumb against his little brother’s mouth. sam would open, sucking softly at the rough pad of dean’s thumb. sam would be out in less than a minute, rocked to sleep by john speeding down an empty highway. dean would smile, wiping sam’s spit off on sam’s pajama shirt as his nose wrinkled up.
it continued well after sam started school, his baby brother nudging his chin against dean’s palm once they’ve laid down for the night in scratchy, stained sheets on top of a lumpy mattress. dean would make any kind noise that wouldn’t disturb their dad in the bed beside their’s, and sam would take it as affirmation. pink lips would wrap around the base of his thumb before sammy’s eyelids would flutter shut. he continued the practice of pulling his thumb away after sam fell asleep. the kid was getting older, and they should of quit it years ago. john already hadnt approved of the habit when sam’s mouth wasnt the only thing making puberty extra hard for dean.
by the time dean was sixteen, he was still letting sam suck on his thumb to go sleep. only now, sam would lay down on his stomach, cheek pressed against dean’s knee as the boy blinked up at him.
it was dean’s own fault, he’d offered sam his thumb when they were watching some cartoon and instead of taking a nap like dean thought he would have, sam had let dean practically hold his head up with his palm while he suckled on the calloused thumb.
dean offered sam the remote, carding his fingers through sam’s hair as his little brother propped himself up on his elbows to scroll through the channels. he picked some action movie, and dean chuckled as he took the remote back from sam when offered, setting it on the side table behind his head.
dean readjusted before sam settled back in, the back of his neck dug into the armrest of the couch, but he barely noticed as sam laid back between his legs, lips parting around a silent, contended sigh as dean slid his middle and ring finger in. sam wrapped his lips around the second knuckles, his tongue subconsciously tracing the seam between the two digits as his half-lidded eyes looked over to the television.
dean didnt pay attention to the explosions and repetitive sound of guns firing, focused on the way sam would occasionally readjust the way his mouth was sucking. he could see it as much as he could feel it, his soft pink tongue taking up too much room as he swallowed the spit that had collected in his mouth when he was in a daze before he’d blush a little more. dean would pet his hair occasionally, barely having to focus on not letting his blood rush south. it was like muscle memory at this point around his little brother.
sam would gnaw softly, barely paying attention, and dean would hiss every time his teeth dug in a little too much. sam would run his tongue over the base of his fingers, eyebrows drawn together in a silent apology. it made dean feel dirty, pulling his fingers out of his baby brother’s mouth as he wiped his fingers off on the shoulder of sam’s shirt. “lunch time, kiddo?”