Why is my dad such a pissy b*tch?

i kinda diagree with the other people. Your dad has no right to yell at you for just letting somone bring a gift. And the guy is just stupid for buying your sister a gift if she is over him. He isn't being led on he is just giving a gift...SO WHAT? I dont understand why it was your fault anyway. But the only thing is i think u should stay out of their realationship so you dont get yelled at. Hope this helps :p