Thirty-four weeks born baby seven months will not sit not roll over is probably normal, should continue to observe a period of time before judging. A full-term baby can sit alone for a while with both hands at 6 months of age. If they can sit still, it will be at 8 months. It is only when your baby is 7 months old that he/she can consciously roll over from the supine to the prone position or vice versa. Babies born at 34 weeks are preterm, and it is normal for preterm babies to grow and develop slower than full-term babies, so don’t worry too much if you can’t roll over at seven months. We recommend that you observe your baby for a few more days to see if he or she can roll over or sit up, and then go to the hospital for a checkup if he or she can’t.