It really depends on the metabollism of your daughter. I know you hate to hear that because you want a definite answer, but I know that I haven't smoked since early July and I am still testing positive for weed. Of course I smoked multiple times every day. If she is being truly honest with you and she is not a daily smoker then she will probably be ok. Weed has a half life of 7 days in your fat, but like I said before, it really depends on her metabollism. Good luck.