How can I get my 20 yearold brother out of my gamut house?

-I'm 13 I can't have a job cuz I'm too young but I still contribute at least 15 dollars a month to gel my parents and I don't even n茅ed to pay rent but my brother and missed out on 2 house payments I think it's 90 bucks a month for him and he doesn't want to look for a job. My mother babies him since he is her only son from her first marriage and she only has two daughters from her second marriage. If I tell my mom he needs to get a job because is an adult and atleast contribute she yells at me and threatens to hit me. And I'm gonna be honest Im not there dream child the only him I do is talk back but I don't steal or date or anything else I just have a smart mouth but I have controlled it in the past month and haven't Said anything. But since we moved to a bigger house( before I shared a roommate with my bro) and he hated sharing a room with me and he only thought about moving out but now since we moved he has his own room and is happy that he is alone and can masturbate freely :p but he doesn't wanna gt a job and me and his steppdad (my dad) hate him. How can we get him to want a job I'm sick of hiss lazy buttwait...your parents make you pay for your room at their house..thats not right!