Level 1: Three-month-old baby’s growth and development At three months, the baby has begun to have some obvious growth and development changes. Their body weight will increase and their height will increase. In addition, the proportions between their heads and torsos gradually become more harmonious. At this point, the baby is able to lift his head and hold it for short periods of time. At the same time, they also begin to become interested in their surroundings and can grasp simple objects with their hands. Level 2