DEAR ABBY: About six weeks ago, I came home from the office and my wife told me that a woman had phoned saying she had some important information about my father. The woman said she lived about 100 miles from here, and she left her telephone number.

Abby, my father died at a young age, leaving my mother with small children to raise. Mother never remarried. Fortunately, she was able to support herself and raise us.My wife persuaded me to return the call. The woman (I'll call her Diane) asked permission to come to my home the following weekend. I refused, agreeing instead to meet her at a local coffee shop.

Abby, Diane is an adoptee who recently located and met her birth mother. She told me that my father was also HER father, which makes her my half-sister! She said her mother had told her that she and my father had been lovers for the last two years of his life. She said her mother never told her lover (Dad) that she was pregnant, and she (Diane) was given up for adoption when she was 5 days old!

I told her that I did not take any stock in secondhand information - that I needed concrete proof in writing. She had none. However, she described my father's physical appearance accurately, knew the names of his friends, the branch of service he had been in, and she correctly detailed the circumstances of his accidental death, which occurred some years ago. I asked Diane what she wanted of me and my family. She said: "Nothing. I just want to know something about my family, and perhaps see some photographs of my blood relatives."

Abby, I was prepared to meet a kook or a con artist. Instead, I found her to be a very gentle, decent person. Now I am totally confused about what to do. At this point, I don't want to tell anyone else. (I am thankful she didn't contact my mother.)

At the end of our meeting, she said, "`Our' father has been dead for a long time. Whom would we be hurting by knowing each other?"

Abby, I am wondering if there is some kind of physical test that could either prove or disprove these allegations? If this woman is really my half-sister, is there any way to verify it? - NO NAME OR CITY, PLEASE

DEAR NO NAME: Ask your physician to recommend a genetic testing specialist. Both you and Diane would be required to submit to physical tests. (Blood samples, for example.)

I agree with Diane. Whom would you be hurting if you know the truth about your blood relationship? There is nothing to be ashamed of. And whether you wish to disclose this new discovery to other family members would be up to you.

DEAR ABBY: I just read the letter from "Puzzled," the man who asked whether he should give his deceased wife's belongings to his soon-to-be new wife. He was concerned about how his three daughters-in-law would feel about it. (He had three sons - no daughters.)

I related to that problem, because a few years ago, I was a daughter-in-law in just that situation. My advice to that man would be to first speak to his sons. There may be some pieces of jewelry or clothing they had given to their mother that for sentimental reasons they would want their wives or daughters to have.

I know from personal experience that it can be very painful for sons to see their father's new wife wearing things that once belonged to their deceased mother. - ANOTHER VIEW

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