Q.Our 7-year-old daughter, a bright second-grader and a good student, is generally quiet, gets along extremely well with her peers and enjoys being with them. Her cousins, who are between 3 and 10, always want to play with her. She can get them to do whatever she wants, but she does it nicely.

However, our daughter has had trouble talking with adults since she was 4 or 5, just as I did when I was young. She speaks with her pediatrician but finds it difficult and stressful to say hello or goodbye to her grandparents, her aunts and uncles -- whom she sees at least once a week -- and even to the grandmother she sees every day. She looks down at the floor and doesn't speak at all.

She also won't say more than "yes," "no," "okay" and "goodbye" on the telephone.

Our daughter is silent in class, too, and won't express or defend her opinions; she won't participate actively and covers up her paper -- especially her math -- so the teacher won't see it. She doesn't want her to know when she can't understand the work.

We have tried everything we can think of to help our daughter.

We have asked her what we should do. We have paid her to say hello and goodbye to adults and charged her money if she didn't. We have put her in time-out. And I have answered for her, again and again, although that seems like I'm just enabling her silence.

What can we do? Who should we see? How can we motivate our daughter?

A.Your daughter needs simple, regular, low-key encouragement, not criticism or corrections.

She needs to be evaluated by a child psychiatrist, a child psychologist or a speech-language pathologist -- someone experienced enough to recognize and treat her problem.

He may first want to rule out a speech disorder, a severe psychiatric disorder and a trauma, as well as pervasive developmental disorder, and then, knowing that she can be fluent and that her problem has persisted for several years, he may tell you that your daughter has selective mutism -- a social phobia.

This anxiety disorder, which affects girls more than boys, comes from extreme shyness, fear or embarrassment, but the problem is neither serious nor remarkable, especially in children who have a history of shyness and anxiety in their families, and especially in the first and second grades.

The symptoms of SM begin gradually, usually between ages 1 and 3, when a child may grow afraid of certain people and refuse to talk in certain settings, but the problem is seldom recognized or diagnosed until she starts school.

Even then, the intensity varies from child to child and setting to setting, and so do the symptoms.

Although SM children can understand what they hear and can speak normally in some social situations and with some people, they may not speak or make eye contact or show any facial expression with others or they may fidget a lot or stare at the floor or nod their heads in response to a question or point or stay absolutely still until someone can guess what they want.

Although selective mutism isn't a learning problem, it can interfere with learning if the child can't ask questions at school. Therefore, it needs to be addressed early. Although SM can disappear on its own, it also can last into adulthood and may cause depression or panic attacks.

Fortunately, it is quite curable.

According to the research, cognitive-behavioral therapy -- and sometimes an anti-anxiety medicine -- is the most effective treatment, and many parents have their SM children see a speech-language pathologist as well.

There is much that you can do, too.

Encourage your daughter to curtsy to grandpa, or give a wink, rather than say hello or goodbye, and ask the teacher to have her collect the papers in class, instead of reciting a poem. And when you must correct your child about her manners, be gentle, because even a mild reprimand seems forceful to a child whose sensitivity level is on high alert.

If you don't make an issue out of her problem, if you praise her fully and frequently for every smile she gives, and if you let her body speak for her when words cannot, her problem will begin to diminish.

For more information on SM, check out www.selectivemutismfoundation.org and American Speech-Language Hearing Association's Web site, www.asha.org, or call the latter at 800-638-8255 to order its $9 pamphlet "Working With Children Who Have Selective Mutism."

Questions? Send them to advice@margueritekelly.com or to Box 15310, Washington, D.C. 20003.