It is often thought that a six-month old baby who does not roll over is not necessarily abnormal. If your baby’s motor development is delayed, this may result in your baby not being able to roll over at six months, which is not necessarily abnormal. Generally speaking, babies can gradually start to learn to roll over within four months, and can learn to roll on their side at the very beginning. In addition, there are some individual differences in each baby, the baby rolls over later there may be some factors, such as the body fat baby, roll over movement later. If the baby wears more clothes in winter, the baby’s movement is not convenient, may turn over later. If the baby six months can not complete the side roll, need to be alert to the possibility of large motor development backward, you can go to the hospital in a timely manner to the Department of Child Health consultation, clear cause of the disease to give targeted treatment or treatment.