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by Abigail Van Buren

DEAR ABBY: I wrote to you 26 years ago about my stepfather and my brother. Now I'm writing to you about my son -- I'll call him Lewis. He's my only child and a junior in high school. His father and I have been divorced since Lewis was 2 years old, and he has lived with his father, who is principal of a large high school, for several years.

Lewis is intelligent, but in spite of that, he struggles to maintain grades high enough to keep himself eligible to play sports. I could accept that, since his father was a late bloomer, but I have trouble with his lying. Lewis constantly cons his dad, me, his teachers and his friends.

Since I live 2 1/2 hours away from my son, I cannot be a daily influence. We talk frequently on the phone; however, we don't see each other often. I used to enjoy our telephone conversations, but about three years ago, I realized he was lying to me. It's getting worse -- to the point that I cannot believe anything he says, and that's breaking my heart. Of course, Lewis denies telling lies.

I want to help him, but I don't know how. Abby, this seems to be a family trait. His father, his grandmother and his aunt are liars, but they won't admit it -- they just keep on lying.

What will the future hold for Lewis if he continues to lie? Will he grow out of it? How can I help him? Does he need psychiatric help? -- OHIO MOTHER

DEAR MOTHER: Evidently lying brings more benefits to your son than telling the truth. Lying is habit-forming. Furthermore, a liar continues to lie until he actually believes his own lies. There may also be a psychological reason for the lying.

Obviously, his future will be in jeopardy if he continues to lie. "Outsiders" will not be as forgiving as his family, and he will surely lose friends (and probably jobs) when he gets caught in his lies.

Will he grow out of it? Not unless he is consistently confronted by his family when he lies, and gets professional counseling. Insist that he get into a program of counseling, and when you catch him in a lie, point it out and insist that he tell you the truth.

P.S. His poor performance in school is another indication that he could benefit from counseling.

DEAR ABBY: I am 22 and recently broke up with a longtime boyfriend. I have been reintroduced to someone with whom I went to high school. However, I didn't know him well back then.

Abby, this man says all the right things, but I'm not sure how to tell the difference between sincerity and the "lines" men use these days. Do all men say the things a girl wants to hear just to get what they want? Is it possible to tell the difference between sincerity and these "lines"? Are there any telltale signs I should watch for? -- LEERY IN VIRGINIA

DEAR LEERY: The best test of sincerity is time. Watch for inconsistencies and observe whether they always result in him getting what HE wants, rather than in what makes YOU happy.

If he's still saying "all the right things" after a couple of months, the odds are that he's sincere and you are a lucky lady.

What teens need to know about sex, drugs, AIDS, and getting along with peers and parents is in "What Every Teen Should Know." To order, send a business-sized, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby, Teen Booklet, P.O. Box 447, Mount Morris, Ill. 61054-0447. (Postage is included.)

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