Delayed speech development stems from variety of causes

Language development begins in infancy. When parents lean over a 3-month-old to say, "How're you doing?" the baby responds with a wriggle, then a smile. Parents smile back, and this time the baby coos.

The rhythms of communication are set up in the second and third months with smiles and vocalizations like these. A baby who isn't communicating in this way may be sending a warning. There may be a delay somewhere in the process of taking in sounds (as well as gestures and facial expressions), understanding their meanings and responding appropriately.

Or there may be a hearing problem. Recurrent ear infections can interfere with a baby's hearing and, as a result, with learning to speak. Fortunately, there are treatments available that can help.

As a baby gets closer to his first birthday, he will begin to vocalize, making sounds like "ma-ma" and "da-da." If a child is not doing this, it may be another early sign of a speech problem.

Sometimes a delay in the coordination of tongue and mouth muscles prevents a child from reproducing the sounds he hears.

When a 9-month-old cannot call a parent to him, he is already missing out on important experiences. A child this age should also be pointing with his index finger as a nonverbal form of communication. A delay in this skill may be due to a number of causes.

By 18 months, a toddler should be pointing at objects and vocalizing with a vibrant, demanding tone. (This is the sign of a normal larynx.)

If a parent holds up an object, the child may use a word to name it. If not, parents can try several maneuvers: They can hold out a toy and say, "Tell me what this is." Or they can read a familiar book with their child, point to a picture and ask, "What's that?" If the child says, "Cat," they can ask: "What does the cat say?" "Meow!"

By the time she is 2, a toddler should have the ability to understand two commands and respond to them: "Go to the couch and sit down." She should be able to vocalize with a clear voice. She should be able to imitate words, name familiar objects when asked and even put two words together — a noun and a verb, such as "Mommy go."

Adjectives and adverbs come in the third year, and they are thrilling to both the child and her parents. "Pretty baby."

The timing of language development varies from child to child, but if a youngster has not reached these milestones, his parents should talk with their pediatrician about setting up a speech and language evaluation.