<< Shoot her. 🙂
Honestly, I've seen worse cases. Your sis is just a mild one. 😛 >>
True.
But Stefan, aren't there times when she does something nice for you, for no reason at all, not trying to get on your good side or get something out of you? Just those times, every once in a while, that you feel you want to hug her and say, "Thanks, *inset name her*." just because you know it will suprise her and make her feel ashamed for the things she has done before?
If not, then the cure for her is, oh, say, 12 guage or 20 guage...depends on how much of a mess you want. 😉 😀