Introduction When a baby turns over at four months, it is an important milestone. The baby\’s physical development and movement coordination will be improved. However, mothers may be worried if their four-month-old baby does not turn over in time. Today, we\’ve asked experts to offer helpful advice to help moms take better care of their babies. Timetable for Baby Turning Over Most babies start rolling over within three months of birth. At four months, babies begin to have better head control and muscle strength, which is the ideal time to roll over.