My opinion is this is not the first couple times she tried this if it was the first time she would have been scared to try it again, because the first time she had been caught. When everyone goes to bed for the next few nights put a piece of tape at the top of your front and back doors if the tape is ripped in the am someone left during the night... Then ground her for as month and try it again, dont tell her how you know shes getting out though tell her you checked her bed. If she makes a fuss about you going in her room you were looking for a cat.... and its your damn house!!! This should work hope it helped.