Is It Standard for Sports Shows to Have Brothers?

There are two things that Itoshi Yuu hates or conflicts with. The first is team sports, especially football. The second is seeing close brothers and sisters in other people's families, especially twins. These two factors are related, and it is very simple to understand. After all, no matter who you are, if you have two brothers who have almost severed all ties with their family because of playing football, it is natural for them to have some emotions in their hearts. * Miyaji: Although volleyball is a team sport, I have no interest in football. Although I have a twin brother, my relationship with him is not good, so... So, will you hate me? ** I want to write some sports stories There will probably be mainly volleyball, blue locks, skateboards, and maybe strong winds The cp may be Miyaji or Kakuname... Or maybe there are bones... I haven't thought of anything. Purpose: do some exercise