If 2 teenagers end up doing drive by shooting on each others houses, all because their fathers were in gangs that did the same back in the day and thats the lif

If 2 teenagers end up doing drive by shooting on each others houses, all because their fathers were in gangs that did the same back in the day and thats the life the kids grew up in, how are you going to assign who is at fault? To either kid, the other side started it.