author's note : No, the boys don't belong to me, neither does John or anything Supernatural, it's all WB and whoever's property.
Slight AU, just because I presume that Dean and Sam sleep in a hotel outside of Livingstone after a year of hunting together. Meh. There's been farther stretches.
The first time Dean watched Sam fight with his dad, he was seventeen years old. Sam decided he wanted to join the swim team, which meant two morning practices a week, on Tuesdays and Thursdays, practices after school every Wednesday, and competitions every second Friday until the semi-finals. At first their Dad just looked at his youngest son calmly, then quite simply said "No." Sam looked back at him defiantly, and a nauseating silence settled over the room. From there, they erupted into a torrent of screaming insults. Dean slunk into the corner, horrified at the fiery gleam in his brother's eyes and the deadly calm reflected in his father. Sam stormed around, throwing his dad's hunting equipment and lamps off whatever shelves or tables he could reach. John stood near the middle of the room, occasionally crossing and uncrossing his arms, fists clenching and unclenching as he watched Sammy stomp around.
That night, Dean hadn't been able to sleep. Sam slammed the door to his room and refused to talk to their father anymore. It was the first time Dean had heard his brother yell "I hate you", and he couldn't help but feel the blow himself. After all, wasn't he part of the lifestyle Sam rejected so vehemently? It felt like someone had punched a hole in his chest.
Six hours later that night, John Winchester awoke to the sound of a strangled scream from his eldest son's room. Instinctively grabbing the loaded shotgun from his dresser, John bolted down the hall, his heart pounding through his chest. He shouldered Dean's door open, gun at the ready, only to be greeted with Dean was laying in his bed, looking up at the ceiling. The sight should have been relieving. It made his stomach churn. In over a decade of hunting, John had never heard his son scream like that.
"Dean?" John approached the bed carefully, methodically checking the room around him and shutting the door with his heel. Dean's window was closed, there were no drafts, no unearthly cold floating in the room, nothing making noise in the locked closet. Dean's box-spring mattress on the floor prevented things from lurking under his bed. A quick glance up revealed nothing on the ceiling.
"Dean?" He asked again, still presented with silence. "Is everything alright?" Dean made a small, muffled gagging noise, his entire body tense, but completely still except for the panicked look in his eyes. Without removing his gaze from his son, John inched towards Dean's large wooden desk, opening the middle drawer with one hand to grab a small bottle and some rope.
"Dean..." The tone was more cautious now. "You need to answer me." He got an answer this time, but it was more unsettling than the silence. A low growl emitted from the bed, with an eerie clicking noise to disclose it's otherworldliness. Cursing under his breath, John carefully knelt on the edge of the mattress, still speaking in a low, smooth tone.
"Dean, I need you to help me," he said slowly, a pit forming in his gut. "Dean, can you hear me? Give me a sign- blink, or nod your head. Anything, Dean." Nothing. Dean was stock still, even as John carefully bound his wrists, layering a miscellaneous piece of clothing from Dean's floor under the rope. Sam had appeared quietly in the doorway behind them, sheepishly wondering why his brother had screamed. John didn't notice as he looped the rope through the headboard, securing it with knots.
"Dean," he reassured one more time, wishing his son would give him even the smallest response. "Cristo," John muttered, fearing the response he knew was coming. Dean flinched. Clenching his jaw, John braced himself.
"I'm sorry, son," he whispered, and as he raised his hand over Dean's chest a splash of holy water trickled from the bottle. A wave of cold washing over his hand made John shudder, and Dean lurched suddenly, steamy smoke hovering over his now damp t-shirt. He started to tug at his bonds, legs thrashing wildly as he tried to kick himself free of the bed. His cries were still oddly muffled, but as he jerked his head violently from side to side they were agonizingly vocalized, his raw scream filling the room. It ripped at John's heart to hear his son shout in pain, but he let another thin stream of water drop, clenching his jaw. Dean bucked and yelped again in what sounded like pure, human panic.
"No! Please--" Dean shouted, and confused, John's hand wavered, knowing the pain holy water would cause could only hurt a demon in him. Another wild thrash, and Dean fell still again, green eyes still locked straight above him in terror. Before John could wonder if it was a trap, Dean let out a shattering scream. His head jerked to the side as four long slashes ripped across his cheek, immediately dripping blood down his chin and neck. John jerked back in confusion, nearly dropping the bottle of holy water. He raised the shotgun, but had nothing to point it at. Dean arched off the bed, crumpling back down a second later as four more deep gashes opened across his chest, slicing through his shirt like butter and soaking his chest red. John stood beside his son's bed, close to panicking as he realized that whatever was hurting Dean, it wasn't in him, and he couldn't see it. Shotgun at the ready, John shouted whatever came to mind: curses, exorcisms, protection spells, and a few "the power of Christ compels you's" tossed in the mix. He wasn't sure why, but a dark shape materialized over Dean and John didn't notice his younger son's arms around Dean's shoulders as Sam ducked under him and threw himself across his brother. Slowly, at first, like someone had turned a smoke machine, the shape twisted into a sinewy silhouette; a large, jagged back hunched over a wide, fang encrusted jaw with lanky, muscular black arms and long claws. John only took it in for a second, it's smoky skin like wrinkled black leather, before putting a shot of rock salt through it. An unholy shriek filled the room, then dissipated, leaving the three Winchesters in silence.
It took Dean three weeks to heal. John had to stitch him up personally, not wanting the questions or cost of a hospital. Sam sat by his brother's bed, refusing to go to school for two days and completely forgetting about swim practice. On the third day, his father dragged him out of the house, threatening that his grades would suffer, and what good was a hunter without brains. At the time, John never considered that Sam would one day leave them for his education. Sam went, but refused to smile or talk with his friends at lunch, because was the only one who would admit what probably happened to his brother. Dean had been emotionally disturbed by their fight earlier that night, and it left him unstable, and alone: a perfect possession opportunity. Because of him.
Dean slipped in and out of foggy dreams for the first week, glad that his dad felt bad enough about what happened to give him a flask of vodka to down before he was stitched up by hand. John couldn't figure out what it was, and didn't have the heart to tell Dean. Once Dean got on his feet, his father tried to avoid the occurrence. Dean only asked about it once:
"Dad?" John looked up from his paper.
"What was it?" John paused, switching the page of the newspaper calmly.
"But, what kind-"
"It's gone, Dean. That's all that matters."
That was three days after Dean was allowed out of his bed. Ten years later, in a motel just outside of Livingston, Dean realized he would have to find out for himself.