hi rikux
it is great that you want to help your sister and mother but that is a big responsibility to have on your shoulders. it would help if you could talk them into going to counseling. learning some communication skills could be helpful for your mom and sis/sis and bf. you can look up reflective listening and i statements if you want to give them some tips. your mother may need to learn some parenting skills such as logical consequences and being consistent with follow thru if she wishes to manage your sisters behavior. welcome to psych central. you will find we have several forums where you can post about your concerns and receive feedback from other members. you will get a lot of support here. again, welcome