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Physical Development of Babies

African American mom and baby

A lot will happen in your baby's first 12 months of life. Before you know it, your tiny, "helpless" newborn baby will be a person in his own right, able to move around and communicate. This section gives a detailed description of your baby's growth and physical development in his first year.


Most healthy, full-term newborn babies double their birth weight by four months and triple it by their first birthday.

Keep in mind, though, that all babies grow at their own pace. A small or large baby may be perfectly healthy. Also, babies have growth spurts and fluctuations in their rate of weight gain.

Motor development

All babies develop according to the same sequence of events. For example, all babies learn to sit before they learn to walk. However, some children reach developmental milestones such as sitting and walking early, and others later.

Babies generally develop from the top down. The first thing to develop is head control and strengthening of the neck muscles. Later, hand coordination develops, which allows a baby to pull himself forward before learning how to crawl. Once a baby has better control of his lower body, he can use his hands and knees to crawl. All of this happens in preparation for learning to walk.

A baby develops as his central nervous system matures. Along the way, many of the primitive reflexes he had as a baby, such as the grasp and walking reflexes, are lost. These primitive reflexes need to disappear in order for a baby to learn to move himself voluntarily. The walking reflex, for example, disappears by the end of the first month of life. The grasp reflex starts to disappear at two to three months of age. Also, while a young baby wildly moves his arms and legs in every direction, an older baby learns to make specific responses.

Vision, hearing and communication

Your baby's eyesight, hearing, and communication skills will develop over his first year of life. While newborn babies can only see things about 25 cm (10 inches) in front of them at first, their sight improves to near adult levels by the age of eight months. Newborn babies can hear rather well at birth, and this, along with their ability to respond to sound and their communication skills, improves throughout the first year.