My 6 month old is always placed on her back to sleep. Most nights she needs to be rocked to sleep and once asleep in my arms I will go to put her down in her cot, when doing so she sometimes turns her body onto her side so by the time I place her down she is already on her side and not her back. She is an extremely capable roller but my question is, should I pick her back up and attempt to place her on her back or leave her on her side?