The first year of an infant's life is filled with tremendous growth and development. There is a range of what constitutes normal acquisition of the various milestones. Below you will find a summary of social-emotional growth, the acquisition of language, and the development of fine and gross motor skills during the first year of life.
Progress varies among babies, so please consult your pediatrician for further information about these milestones. A great resource to have on hand is Dr. Steven P. Shelov's book, Your Baby and Child.
Newborn babies look about with a glassy gaze at a brand new world. Early on babies show a preference for looking at human faces. The ideal distance for a baby to focus during the first couple of months is about eight to twelve inches -- the distance between your baby and your face when you hold the baby in the crook of your arm.
Jean Piaget, noted psychologist, characterized the early months as the "sensorimotor phase," which aptly describes the activities of the 1- to 3-month-old child who explores the world through his or her mouth. The spontaneous, random smile of the 1-month-old child develops into the socially responsive smile at around 2 months of age. The baby is learning to recognize familiar faces and is eager to greet them. The 4-month-old baby is able to sustain longer periods of social contact and can express a fuller repertoire of pleasure and displeasure.
From about 6 months of age onwards, babies begin to develop the Piagetian concept of "object permanence" (baby has a more fully developed mental image of people and objects that continue to exist even when the person or object is not currently visible). A baby knows when parents leave the room, and now the baby will more actively seek them when they are not present.
Becoming wary of unfamiliar people, or of friends and relatives who are not often seen, typically begins around 8 to 10 months of age. The term that has been coined for this wariness is "stranger anxiety," and you may want to warn visitors not to rush to hug the baby, but to give her time to warm up to them.
As the tension around separation often intensifies between 6 and 12 months of age, peek-a-boo becomes the perfect game for playing out some of these feelings. Babies become excited by the disappearance and reassuring reappearance of a familiar face. As parents and other important caregivers come and go throughout the day, it becomes particularly important to let your baby know when you are going out and that you will come back soon. Sneaking out in the hope that this will lessen the pain of separation often backfires (suddenly disappearing may make baby anxious).