What milestone is expected for a baby at 2 months of age?

At 2 months of age, a baby's physical development typically includes the ability to lift their head while lying on their stomach, a milestone known as "prone neck extension." This ability is an important indicator of developing muscle strength and control. At this age, babies will usually be able to hold their head up to about a 45-degree angle while in the prone position, which signifies that their neck and shoulder muscles are strengthening.

The other milestones mentioned—rolling over, sitting up, and crawling—are more advanced skills that generally develop later. Rolling over usually occurs around 4 to 6 months, sitting up around 6 to 8 months, and crawling typically begins around 7 to 10 months. Therefore, lifting the head off the ground while prone is the milestone that aligns with expected development at 2 months of age.