This is something that popped into my mind after rewatching 4x01.
I don't own Glee, and English is not my first language but felt more natural to write.
It's pretty short, but enjoy
Starring into space Jake sat on the bleachers. It had been close to a week since he refused to join Glee club after Mr. Schue's explanation. Sometimes he hated his temper, but apparently that was the only significant part of the Puckerman DNA when it came to character.
Since that day he spent most afternoon in the dark of the auditorium watching the choirs practices, sometimes he felt like a stalker. But music was the love of his life, it was what kept him sane when his mother started drinking after Puckerman senior upped and left. The only thing he really had of his father was his last name, given his mother had been the other woman. The one he wanted to leave his wife for. His little half sister was the proof of how well that worked out.
It took him a minute to realize the person coming closer and finally sitting down one row above and a few seats away from him. He wasn't in the mood for one of Mr. Schuester's attempts to get him to join, but he chose to just stay silent.
"So Schue called me and said he had someone I should talk to before I left town." Jake tensed up realizing that this wasn't the teacher. He didn't turn around, already having quite an idea who was sitting there. "You know when he told me about you, it was almost funny how alike we are." The younger man was shocked how calm the feared Puck sounded.
"I'm not you Puck. So give up, I won't join that stupid club and become your clone." This was followed by laughing and a hand on his shoulder. "Given that would include a trip to juvie I wouldn't want you to. But believe me when I say Glee club is far from stupid." Jake felt the movement of his older brother climbing over the seats to sit down next to him. "You know the best thing about Glee? It means you are never alone. No matter how much shit you pull you will always be welcomed back with open arms." Jake simply rolled his eyes.
"Just because it made you a saint doesn't mean it's right for me." Again Puck chuckled. "Believe me I am as far from a saint as they come, but it helped to sort my stuff out. The way I see it both of us have been screwed over pretty good by our old man. It's nice to have a positive male role model for once. " Puck gave it a second thought. "See it like this: If I had found out 3 years ago that I have a half-brother that's older than Sarah, I would have reacted with rage. Today I know it's not our fault what happened."
"Just because we share the same DNA doesn't make us family." "True, but I might be the only person who knows exactly where you come from. Maybe we aren't family in the original kind of way, but I like the idea of someone looking out for Sarah once I am gone. And who would be better than a younger version of myself?" Jake hoped Puck was only joking. But he kind of liked the idea of having a younger sibling to look after.
"I won't tell you what to do, I know us Puckermans don't handle that too well, but think about it. There are only a few good things we get from our old man and our amazing as fuck music skills are one of them." For the first time Jake looked up seeing the famous Puckerman smirk. They both stood up and walked over to the school building. Jake having one last question.
"Has Mr. Schuester really told you we are brothers?" "No, he said there was a troubled kid who reminded him of me, but do you own a mirror?" That actually made Jake laugh as well.