It is recommended that atleast for the first six months the baby should sleep on the back.

same mre sath bho yahi dikkat h wo 3 mnth se ase h soraha h

she is sleeping in day time after massage..and some times in afternoon

Yes as long as baby has good control of head and neck no issues with sleeping on tummy. Don't put pillows or blankets near head area.I remember I would also check on my baby a couple of times in the night!

only on back sleep is recommended