My 6 month old daughter has been napping in my bed since day one. She has always done well. She sleeps for 2 hours for 2 naps a day right now. But, now that she is beginning to move I am nervous that she will roll herself off my bed. Any thoughts on how to transition her to her crib for nap times. (She sleeps in her crib through the night but has always napped in my bed.) :?