I agree with the other posters. They have offered great advice. I would watch her and ambush her. She know the rules and is breaking them intentionally- even at her age- whats worse is she is bringing her sister along for the ride. When I caught her I wouldn't say a word, just give her a swat, take her down, and walk off. Then watch again. I would make it your duty for at least one whole day to catch her. That is just how I would handle repeat offense like that. As far as removing the items- maybe some of the more expensive items, but replace them with cheap lip glosses or something. I don't know if you are a Christian or not, but my thought are God did not put the Tree of Knowledge of Good and Evil out of reach, he put it in the middle of the garden. Well, there is my 2 cents. ;)