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by Abigail Van Buren

DEAR ABBY: I recently had major surgery. After the operation, my surgeon advised me that I had a genetic defect which had complicated the procedure. He advised me to notify my children so they could be checked for it.

I notified my four children and they all have a similar problem. Here is my dilemma:

When I was in college, I foolishly had an affair with an older man and became pregnant. I couldn't support a child at that time, so I chose to give my son up for adoption. Because of my genetic defect, I decided to attempt to locate this child to let him know about it. I hired a private detective who soon located him, but his adoptive mother had told him I died shortly after he was born.

When I married him 30 years ago, my husband knew I'd had a child, but the subject has been taboo ever since our wedding. None of my children know they have a half-brother.

Should I contact my son even though he thinks his birth mother is dead? I'm sure it would be upsetting to learn that his adoptive mother lied to him. He may need to know about the problem that runs in our family. Please advise me. -- TORN IN TOLEDO

DEAR TORN: Since the information could affect your son's health, it's important that he know about your medical history. You do not have to meet with him to give him the information. Ask your surgeon to write a letter to your son which covers the family medical history.

Your son will probably be shocked to learn that his adoptive mother lied, but he may want to get in touch with you. Many adoptees feel the need to meet their birth parents in order to feel "complete." Experts have told me that the vast majority of birth parents and children who have been reunited were gratified with the outcome.

DEAR ABBY: You printed a letter from a woman asking questions about her grandchild traveling unattended on an airplane to visit her.

You might be interested to know that the American Automobile Association has prepared a brochure addressing this situation. It's titled "Flying Alone: Handy Advice for Kids Traveling Solo." Parents interested in obtaining a free copy of the informative brochure should send a long, business-sized (No. 10), self-addressed, stamped envelope to: AAA, Flying Alone -- MS75, 1000 AAA Drive, Heathrow, Fla. 32746. -- JERRY CHESKE, DIRECTOR, PUBLIC RELATIONS, AAA NATIONAL OFFICE, HEATHROW, FLA.

DEAR MR. CHESKE: I think the little booklet is a dandy for any parent who is contemplating sending an unaccompanied child anywhere by air. It gives helpful tips about what to expect at the airport, lists the various age restrictions for unaccompanied minors, and offers suggestions concerning what to say and do prior to the child boarding the plane. Thanks for letting my readers know it's available. And the price is right -- it's free!

DEAR ABBY: I am 30 and engaged to a 28-year-old woman I'll call Sharon. Her best friend, "Janie," asks very personal questions, like "How often do you two have sex?"

Sharon will lie to her and reply "Twice a month." I'm not there when Janie asks these questions, but I hear about it afterward from Sharon. I resent the questions and prefer that Sharon ignore her and pretend she didn't hear the question.

Sharon reasons that if she tells her friend a lie and the woman knows it's a lie, it will keep her guessing. I feel it is none of her business and doesn't deserve a response. How do you think this should be handled? -- BOB IN NEW HAMPSHIRE

DEAR BOB: Ask Sharon, "What's wrong with telling your friend that you do not care to respond to such personal questions?"

For everything you need to know about wedding planning, order "How to Have a Lovely Wedding." Send a business-sized, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby, Wedding Booklet, P.O. Box 447, Mount Morris, Ill. 61054-0447. (Postage is included.)

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