My parents are seperating and I have my father's last name. My parents were never married just engaged but I believe they're seperating by the way they argue and my mom is saying she's kicking him out. My father has been drunk for the past two weeks and been a real er.... Jerk to my mother and I don't want to have the last name of him anymore he's irritating. I'm 13 years old, how long and how do I change my last name legally (I know I'll need my parent consent) Also which name could I get(I was thinking and on my mom's side there's my real grandpa's last name, my step-grandpa's, my mom's marriage last name, and my grandma's real last name(Which I do not know) Please help and don't say things about how my age I shouldn't care about my last name or things like that. Also don't comment on my father please..