Advice on sleep and head

DeLaLi

LO is almost 4 months and rolls from tummy to back only. He doesn’t enjoy tummy time and has very little flatness on the back of his head. Doc suggested putting him on his belly to sleep at night. I’m scared and never heard of this. My daughter belly slept, but I started her from young because she just wouldn’t sleep. He sleeps well on his back, minus this little regression we’re going through, but I don’t want his head getting flatter.

ETA: I spoke to my MIL who’s a nurse and she suggested to put him on his side and just put a receiving blanket behind him so that way he’s not placed on his tummy and then he gets some time off his back. His head isn’t severely flat at all so we all assume it’ll work itself out very soon once he’s more mobile.