C.O.
As long as she is strong enough to pick her head up off of the mattress I wouldn't be too concerned about her falling asleep on her tummy. If she cannotlift her head, I would roll up two small recieveing blankets and place one on either side of her when you lay her down to go to sleep. That will make it difficult for her to roll over and then you won't have to worry and she won't get so mad. Good luck, and Enjoy her!!!