At 4 months, what milestone should a baby typically reach?

At 4 months of age, a baby typically achieves the milestone of rolling over. This developmental stage marks significant progress in motor skills and physical coordination. Around this age, infants begin to develop strength in their neck, back, and arm muscles, enabling them to pivot and shift their bodies. Rolling over generally occurs from tummy to back first, as babies learn to shift their weight and use their arms and legs to turn.

The other milestones listed occur later in an infant's development. Sitting up independently usually develops by around 6 months, crawling typically begins between 7 to 10 months, and standing with support often occurs around 9 months. Thus, rolling over at 4 months is a clear and appropriate milestone for that age.