Sleeping positions

Chloe

I know it is always preached that the back is the safest position for a baby to sleep and I absolutely agree, however my baby is 5 months old now and is rolling non stop. I found when I lay her in her crib at night on her back the moment I leave the room she is asleep on her stomach her arm underneath hee head almost propping it up like I would underneath a pillow. She also likes to sleep with her butt in the air in like a crouching position. I was wondering if I should keep turning her to her back or let her roll into a position she has been enjoying?