DEAR ABBY: I am in urgent need of advice. My 26-year-old, college-educated daughter just told me that she and her 25-year-old first cousin are in love and are considering marriage. Isn't that considered incest? These two have always shared a close friendship, but our families have lived in different states, and they have seen each other only for family celebrations.

Seven months ago, my daughter moved to the city where her cousin lives, and they decided to share a two-bedroom apartment.Abby, the idea of these two marrying has upset my husband and me. We have heard that if first cousins marry, they should not have children. Also, isn't it true that there are only a few states that permit first cousins to marry? (If so, which ones are they?)

I am hoping these two kids will come to their senses and break up. - CAN'T SLEEP IN MARYLAND

DEAR CAN'T SLEEP: First cousins may marry in Alabama, Alaska, California, Colorado, Connecticut, Florida, Georgia, Hawaii, Maine, Maryland, Massachusetts, New Jersey, New York, Rhode Island, South Carolina, Tennessee, Texas, Vermont, the District of Columbia and Virginia. And in Wisconsin, first cousins may marry if the woman is 55 years old or older.

However, if first cousins marry and decide to have children, they should consult a genetic counselor.

DEAR ABBY: I have to tell someone about my mother, who is a grandmother.

Every year at Christmastime when she visits her sisters' and brothers' homes, they send presents home with her to give to her grandchildren. All these presents are gift-wrapped.

When she gets home, she carefully opens all of the presents, examines them, then she rewraps them in the same paper.

I have suggested to her that this is childish. What do you think, Abby? Maybe she will listen to you; I know she reads your column. - D.K.

DEAR D.K.: Your mother's behavior is not only childish, it's also nosy and underhanded.

DEAR ABBY: What do people get out of key-scratching a nice car? I drive a red Mercedes, which I keep in my garage. But when I leave it in a parking lot at the mall or on the street for a short time, I return to find scratches on the door - put there deliberately. The same thing has happened to my father, sister and to friends who also drive nice cars.

There is nothing I can do to protect my car because the alarm doesn't go off when this happens.

I would like to know why anyone would want to deliberately scratch a nice car this way. - SEEING RED IN TEXAS

DEAR SEEING RED: I don't know, but let me guess. It's nothing personal. You are simply an anonymous car owner who has provoked the ire of a cowardly, mean-spirited stranger who begrudges you that handsome red Mercedes that he or she would like to own.

DEAR ABBY: My 25-year-old daughter has been living with her 36-year-old boyfriend since November 1989. She had a baby girl (his) three months ago and wants to get married. They live in Ohio. Her boyfriend's divorce was final three months ago, and he told her that in Ohio you have to be divorced for six months before you can get married again. Is this true? - HER MOTHER

DEAR MOTHER: No. According to Judge Ron Solove of the Domestic Relations Court (Franklin County, Ohio), after a divorce is final, there is no waiting period before a person is free to marry again. Your daughter's boyfriend is either stalling or is misinformed about Ohio law.

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