Neighbor Trouble?

I have this neighbor that is a year younger than me and she has a brother that is 3 years younger than me. The problem is, is that she invites herself, her brother, and people that I don't even no into MY house, then when I tell her that I don't apprieciate it, she doesn't even care and she does it again.(Plus they eat all my food, then leaves, she doesn't even ask)And if that's not bad enough, her and her brother both hav this disease called, lieing and stealing. Her brother stole my skittles and 25 $$$ from me and lied to me about a million things. and she lied to me, my mom, and my dad. (Plus I hav proof that he stole these things, becuz I have hidden cameras everywhere in my room, and no one nos about them except my mom and dad.) What do I do about her and her brother? PLEASE HELP ME!!!!!!!!!!!!!