When should my baby start rolling from tummy to back?
At about 3 months when placed on their stomach, your baby will lift his/her head and shoulders up, using arms for support. This mini-pushup helps them to strengthen muscles they'll use to roll over.
My daughter started to roll over from tummy to back at 4 months and quickly learned how to roll from back to belly.
At 5 months your baby will probably be able to lift their head and push up with their arms arch their back to lift his chest off the ground. They may
even rock onto their stomach, kick their legs, and swim with their arms. All these exercises help them develop the muscles they need to roll over in both directions – likely by the time they're about 6 months old.
My girl learned to roll from tummy to back at 6 weeks! But back to front didn't come until about 5 months, like you said.