Normal Growth A child's growth not only involves the length and weight of his or her body, but also internal growth and development. Understanding the Teen Brain Parents need to realize the rational part of a teen’s brain isn’t fully developed and won’t be until he or she is 25 years old or so. The Growing Child: 1 to 3 Months At this stage of growth, your baby will gain 1-1/2 to 2 pounds in weight and more than an inch in height each month. The Growing Child: 10 to 12 Months Your child can now says da-da and ma-ma, and possibly two other words, as well. He or she can also make a simple gesture such as shaking the head. The Growing Child: 1-Year-Olds Your child is a toddler now and very active! He or she can climb stairs while holding on and play with push and pull toys. The Growing Child: 2-Year-Olds Speech at this age is becoming clearer. Your child has a vocabulary of 200 to 300 words and can tell his or her age and name. The Growing Child: 3-Year-Olds Most 3-year-olds have lost the rounded tummy of a toddler. Your child can use a spoon well and can wash and dry his or her hands. The Growing Child: 4 to 6 Months This age is very social, and babies begin moving in much more purposeful ways. The Growing Child: 7 to 9 Months A baby of this age rolls over easily from front to back and back to front, and bounces when supported to stand. The Growing Child: Adolescent (13 to 18 Years) Adolescence is a time for growth spurts and puberty changes. Sexual maturation may occur gradually or several signs may become visible at the same time. The Growing Child: Newborn In the first month of life, babies usually catch up and surpass their birthweight, then steadily continue to gain weight. The Growing Child: Preschool (4 to 5 Years) Children at this age begin to understand concepts and can compare abstract ideas. The Growing Child: School-Age (6 to 12 Years) Although friendships become more important at this age, children are still fond of their parents and like being part of a family.