Q) My husband and I are the parents of a lively and intelligent 3-year-old girl.We both work full time, and she is doing very well in a family day-care situation during the week.

On weekends we don't go out without her very often except to play golf during her nap hours. We are satisfied with the situation because she's doing so well. We're happy and when we're with her, we're really with her.

Here's the problem: I am due to go on a 10-day business trip. My boss has never asked me to do this because he is a family man himself and knows I don't like to be separated from my daughter after work hours.

However, our whole section will be involved with this trip, so I must go, too. In a way, I want to go, to be a real member of our team. Our daughter will be at home with her father and the usual baby sitter, which shouldn't be too bad, except that I won't be able to contact her for those 10 days. The work is for the government and classified; my family will have only a central phone contact to pass emergency messages.

What can I do to prepare my little girl for the trip, and what measures can I take to make the time quicker and happier for her? I don't want her to feel I abandoned her. She has only been away from me when she visited grandparents out of town.

A) Because a child reacts to the normal crunches of life much like her parents do, your little girl should do just fine. You're certainly setting a good example.

You're matter-of-fact about the trip; you've accepted the boss' decision without resentment; you've weighed the pros and cons and know you want to be part of the team. By recognizing the necessity of the trip, and its benefits, you've acted with maturity and grace. You can expect your child to do the same.

She'll miss you, of course, and she'll quite likely be distant with you when you get back, but only for a few days.

In fact, you'll probably feel more bereft when you go than she will. This calls for some special treats for you, as well as for her. Take some pictures of her with you, and if it's allowed, a tape of her voice, since you can't telephone.

Just preparing her treats will lessen your own anxiety when you're away.

The tape recorder is a godsend to the parent who must travel. No matter how many fine children's books are recorded by famous actors, your child is bound to like the voices of her own parents best. Make several tapes of yourself reading her favorite books aloud, going at the speed you know she likes and stopping from time to time to point out something she usually mentions, and then give her time to answer. Not only is this a friendly thing to do, but new studies show that the best readers in school are those who have been allowed to talk about a story as it's read to them.

And then there's the gift-a-day program that's so popular in some households, although it comes close to bribery. That's all right. Almost everything has its place in parenthood, sooner or later.

This grab bag of gifts shouldn't cost much money, but it will take some thoughtfulness and enough time to assemble and wrap 10 presents. Or wrap nine of them, if you get that longtime (if often short-lived) favorite, a live goldfish in a bowl. It's a good gift for the first day you're away. Other possibilities include a soap in the shape of a fish; a small umbrella; an old-fashioned magic slate that will erase when she lifts the plastic sheet; a harmonica; a clear wand full of sparkles; a record or puzzle; a party hat or some sunglasses; a book that begins to give a child the concept of the year-round passing of time, like Meg and Mog Birthday Book by Helen Nicoll and Jan Pienkowski (Picture Puffin; $3.50), or the splendid reissue, Over and Over by Charlotte Zolotow (Harper & Row; $7.50). She'll also like some of your castoffs for her dress-up box, including a pair of high heels, and some homemade items, such as six of her favorite cookies or a very simple costume. A bride's veil of white net can be stitched to a hairband or you can cut a Superman cape out of red felt or make a tutu by sewing a ruffle of net onto a ribbon. With Velcro fasteners, she can handle them easily.

And if you want to leave one special present, consider plastic roller skates. She'll use them more for walking than rolling, but at 3, she won't care.

You'll also give your child another present when you go: her dad.

Even though you both spend most of your free time with her, this trip will let the two of them forge a different sort of bond, as she has made when she visited her grandparents alone.

Each time someone comes or goes in a family, the whole chemistry of the family changes, letting new light into old relationships.

Parents are desperately important to a child, but as long as she knows they're coming back, she'll keep her confidence and be the richer for it. Questions may be sent to P.O. Box 15310, Washington, D.C. 20003.