One Shot
Dean was sixteen and Sam was twelve. He knew it was wrong but he was a jock and Sam was this nerdy little twerp, no one even knew they were related until after the entire thing went down.
A few of the local kids were picking on Sam, pushing him around and calling him a loser and a faggot just because he was this lanky, all limbs and no muscles kind of kid. But he was twelve, damn it. What the hell did they expect? The Hulk?
After school on this specific day, Sam was getting the shit beat out of him when he went to pick him up from the middle school he was going to, the high school jocks all over him, kicking him even though the poor kid wasn't even able to get up and fight back. Dean stood back for just a second, hoping Sam would get up, but then someone kicked his brother in the face and that was it. He ran forward and tugged the kid away from him, bashing the end of his gun into his face as blood splattered everywhere, the other jocks trying to pry him away as they yelled at him, "It's just some middle school fag, man! Let it go!"
"That 'middle school fag' is my fucking brother!" Dean snarled at them, all of them backing away instantly as Dean rose to his feet, his bloodied gun in his hand. "And if you fuck with him again, you're going to get exactly what your friend here is getting." he added as he pointed the gun at the beaten kid at his feet, pulling the trigger and sending a bullet into his skull.
After that, the kids took off, Dean got Sam back to the motel and cleaned him off, and they headed out of town the next day with John. No one came forward with the description of the man who shot the 'innocent' seventeen year old teen nor did thy trace the gun back to him since they used fake IDs to get it anyways.
Sam asked about what happened in the town a week later, wondering why they didn't stay to finish the hunt, but Dean just told him that the hunt was a dead end. That John lost all leads and the monster moved to the next town or something.
Ten years later, they hunted and killed that same wendigo.