Q. The recent discussion in your column about the beautiful child has set me thinking again about Barbie dolls. My daughter, 5 1/2, wants one for Christmas. I can't help wondering: Is Barbie a tyrant or does she help a child feel free?

Many parents forbid these dolls because they think they teach an impossible physical ideal. I'd like to suggest that, on the contrary, our entire culture pushes this idea and Barbie offers a release--a chance, for a time, to make the story go the way she wants. Playing with a Barbie doll helps a child let off steam and form a healthy body image, like a 3-year-old wearing Underoos and pretending he's Superman.

Or is this all hogwash to justify buying a Barbie doll?

A. I'm with you, sort of. The homeliest child identifies with Barbie, and so does the prettiest.

This three-dimensional paper doll is so popular because it helps a child imagine being a teen-ager and how she would act in different situations. The same child also is defining herself when she sits relentlessly in front of the television set, watching mindless sitcoms, or pretends to be reading while she's really listening to her parents and their friends.

When a child can tell herself what she would have done and said -- no matter how improbable her solutions -- she will feel that much safer about growing up, for she will have answers. Anxiety is born of uncertainty.

Children need to daydream and, being children, they sometimes need props to do it, whether it's a book, a television show, a real-life scene -- or a Barbie doll. Whether the props have to be as elaborate as Barbie is another question.

To some parents, all dolls are sexist and Barbie is the most sexist of all. This may be true, but it seems to be the blatant gender of the wench that bothers many parents. Somehow the full line of Storybook dolls are more acceptable than one chesty Barbie, dressed or not.

If this is the concern, it's unnecessary. As hard as it is to imagine, children don't think like adults, especially about sex. To a child in the first few grades, sex is anything that's scatalogical while a preteen thinks it's romance. At this age Barbie inspires seemingly endless dreams of fashion and glamor: a safe way to put sex on hold.

Barbie may be chesty but she isn't lewd. She does, however, have serious drawbacks.

The worst about her, or any of the "fashion dolls," is the message that goes with it: It's hard for a child to believe that the best things in life are free when the trappings are expensive.

The second worse thing about giving a Barbie is giving it too soon. You would be denying her all the caring and nurturing that baby dolls and stuffed animals encourage, and 5-year-olds want to give. Since a child looks on a Barbie as an extension of herself, she would be faced with an impossible problem: She couldn't be as solicitous with herself as she would if she were playing mother to baby doll.

To give Barbie this young would invite frustration as well as boredom. As Doris McNeely Johnson says in her book, Children's Toys and Books (Scribner's, $12.95), Barbie not only is fragile, but it would take a dextrous 5-year-old to put her in such fancy clothes and shoes. It also would take a mighty tidy 5-year-old to keep track of them.

For all those reasons, a Barbie is usually inappropriate at 5. A good toy gives pleasure and a sense of achievement, but the first isn't possible without the second.