The way my first son moved in utero, I swore he'd be kickboxing at birth. Of course, like every newborn, all he could do in those early days was flail his tiny arms and legs. His head was so wobbly that if I held him upright in front of my chest, it would bob and weave before finally dropping onto my shoulder.
Babies have a long way to go before they can toddle swiftly across a room. To accomplish each motor milestone -- whether it's grasping, rolling over, or walking -- an infant needs the right mix of muscular strength, balance, coordination, cognitive development, and, especially, desire. Fortunately, "children have an incredible quest for mobility that helps them pull up against gravity and get on their feet," says Gordon Williamson, Ph.D., an associate clinical professor in the rehabilitation medicine department at John F. Kennedy Medical Center, in Edison, New Jersey. Each physical skill your child conquers becomes a building block for the next, and you can do a lot to help move things along. Follow our guide to the milestones your baby will master in the first 18 months of life. (Age ranges are approximate.)Pushing Up: 4 to 5 months
After your newborn has learned to steady her head, she'll begin working on push-ups. She'll struggle to raise herself on bent elbows and later to fully extended arms. "Babies spend the first six months of life gaining control of their posture, which sets the stage for virtually all other movements, including reaching and grasping," says Carl Gabbard, Ph.D., author of Lifelong Motor Development (Allyn & Bacon, 3rd ed.,1999) and director of the motor-development laboratory in the department of health and kinesiology at Texas A&M University, in College Station.
Shifting her weight from side to side, your baby will develop arm strength and coordinate her shoulder muscles. This will eventually enable her to reach overhead and diagonally as well as hold her arms up in the air. With a stable upper body, she will no longer need her hands to support herself, leaving them free to explore. Your infant is also refining head control by holding her head off the floor and turning it from side to side.
Skill builder: Place your baby belly-down on the floor for short, frequent practice sessions throughout the day (not at naptimes or bedtime, however, because of the risk of SIDS).Reaching and Grasping: 4 to 5 months
At birth, your newborn's fists are clenched. In the first weeks, he will wave his arms spontaneously and automatically close his hand around any object placed in his palm. When these reflexes disappear, at about 3 to 4 months, initial attempts to control his hands will be jerky: He'll use both hands to corral an object. By 6 or 7 months, your baby will be better at reaching and sitting, too, which means he can better examine things that interest him. And though your infant can let things simply drop from his hands, he won't be able to release an object efficiently and accurately until he's about 18 months old, Dr. Gabbard says.
Skill builder: Give your baby a variety of objects to reach for. Offer toys that fit in one hand as well as bigger objects that require a two-handed grip. Vary their shape, too: Picking up a ball, for instance, requires different skills than grasping a cube. And place both still and moving objects within reach, sometimes to your child's side, so he must turn his body to grasp them.Rolling Over: 4 to 6 months
As your infant gets better at push-ups, she'll practice reaching in that position. And one time, with a hand up, she may lean just a bit too far to one side and suddenly find herself faceup -- startled but thrilled. Eventually, though, she'll learn to turn over intentionally.
This first awkward flip is called a log roll because the upper and lower halves of the body move as one block. At about 6 months, your baby will be able to rotate her torso; her pelvis will initiate the roll, and her shoulders will follow. Turning at the waist will allow her to look around when she masters sitting and to alternate her legs and arms as she learns to walk.
Once she's on her back, your baby will kick her legs, lift her bottom off the floor, and bring her toes to her mouth -- moves that strengthen her abdominal muscles. Soon she'll master the opposite roll: Lifting her legs in the air, she may fall to one side and scramble right onto her belly.
Skill builder: Give your baby plenty of floor space and time to roll and flip as she pleases. Toys, such as a baby gym, can also enhance development by encouraging kicking and reaching.