if they ask me, only my closest friend. why, because "hey, I'm dating your sister" is a little odd for someone to say who is not close to you. but, since it is not my choice, she could date Charles Hitler(a combination of Charles Manson and Adolf Hitler) for all I care. it would also be weird because I am 13(nothing I say will ever be taken seriously again), and she's 21. so, yeah.