Hi. My 3 week old is only sleeping on her tummy at the moment. Tried a few times with back, but just resulted in crying. Have got a movement monitor on loan from a friend, but still feel a bit anxious about it. My 18 month old always settled himself to sleep on his back, so don't know if I should just leave her to cry it out on her back & hope she'll just get used to it...???? Any ideas??