DEAR ABBY: My sister, "Elizabeth," died recently. She had adopted a baby at birth and insisted that the child not be told that she was adopted.

The "child" is now in her 50s, and we think that for years she may have suspected that she was adopted because she's different in appearance and temperament from other family members.

On the off chance that she has siblings, would it be wise to inform her at this late date of her adoption? I think the reason Elizabeth didn't want her to know was that she was afraid of losing her daughter's affections. I did not agree with that decision, but I honored it while my sister was alive. What are your thoughts on this matter? -- STAYING MUTE IN NEW JERSEY

DEAR STAYING MUTE: Remain mute no longer. Your niece has a right to know her personal history. Adoption stopped being considered a deep, dark secret decades ago. I am sure she will have mixed feelings knowing this was kept from her for so long -- but it's important you share with her any and all information you have so that she can initiate a search if she wishes. At the least, she should know if there is a genetic predisposition to any illnesses in her background.

DEAR ABBY: Is it appropriate for my husband's mother to take him alone to dinner to celebrate his birthday? We have been married for 13 years and have two children, yet she did not include the rest of us. My husband thinks it's because she can't afford dinner for all of us, but I think she should then just order a pizza and have us to her house.

This is the third or fourth time she has invited him to dinner without including us, and I am hurt that I am excluded. Should I not take this personally? -- LEFT OUT ON THE LEFT COAST

DEAR LEFT OUT: If his mother wants alone time with her son, she could invite him to join her for lunch that day so they could talk privately. As it stands, I agree, you are being excluded -- and I'm curious about why your husband would go along with it.

DEAR ABBY: We moved to a small (six-house) cul-de-sac last October, and a few weeks later we were outside raking leaves. Two of our neighbors were outside as well, and no one introduced themselves or even waved.

We left a very friendly subdivision and were hoping to find the same in our new neighborhood. We are just looking for a smile, and someone to watch our house if we're out of town, etc. We'd be happy to return the favor.

Any advice for this new neighbor? When we bought the house we were told that all the neighbors were friendly and about our age. -- UNHAPPY IN THE CUL-DE-SAC

DEAR UNHAPPY: Please do not make a snap decision about your new neighbors. The "natives" may, indeed, be friendly. They may not, however, be as outgoing as your former neighbors were.

My advice is to go to each of them, introduce yourself, perhaps invite them over for coffee, and let them get to know you. Relationships take time to build, and not everyone may respond as you wish, but I'm betting some of them will. Hold a good thought.

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DEAR ABBY: I couldn't believe my eyes when I read your reply to "Second-Guessing Myself in S.C." (Dec. 18), who reported her son and his friends for getting high on campus. You said she should have informed the boys' parents so they had the option of dealing with the matter themselves -- and she owed those parents an apology.

As a drug prevention professional, I know that "Second-Guessing" was correct! Drug use is unlikely to stop unless there is an intervention. At the school where I work, a suspension for substance abuse is followed by a mandatory use assessment and, if recommended, substance abuse education and/or counseling. The anger that the friends' parents directed toward the writer of that letter needs to be seen for what it is -- enabling. If those boys were caught high on a job, they'd be fired.

Please let your readers know that you made a mistake. Encourage parents to take a stand, talk with their children often about the dangers of drugs, and let their children know that if they use drugs, they'll be held fully accountable. -- MIDDLE SCHOOL DRUG PREVENTION SPECIALIST, FAIRBANKS, ALASKA

DEAR DRUG PREVENTION SPECIALIST: Perhaps this column can be used as a starting point for that conversation. A lot of folks were upset about my response to that letter, in which I told the writer I thought she had jumped the gun in reporting the problem to the school administration, and that she owed those parents an apology for jumping the gun. What I failed to take into consideration was that teachers are mandated by law to report anything they see that they know to be against the law. Mea culpa! Read on:

DEAR ABBY: Would you have criticized that parent if the students were driving drunk? Shoplifting? Committing acts of vandalism? I think she should have reported them to the police as well as the school.

That the other parents were upset because their children were punished administratively is one of the reasons that so many kids get into trouble today. Their parents excuse the misdeed and fault the person who does take some positive action. Certainly, I expect parents to stand by their kids when they're in trouble, but being supportive does not mean excusing or covering up illegal behavior. Students need to learn accountability for their misdeeds, and not expect parents to bail (no pun intended) them out of their wrongdoings. -- RETIRED STATE TROOPER, ALLENTOWN, PA.

DEAR ABBY: As the mother of a boy who died of a drug overdose, I reacted strongly to your answer to "Second-Guessing Myself."

Those teens were breaking the law, and eventually their drug use could result in their own, or someone else's, death. Those students were using illegal drugs on school grounds. That mother did her son a favor by not putting him in a position where he had to rat on his friends, and believe me, the police would have put plenty of pressure on him to do so.

They did the crime. They need to be responsible for their behavior. She did the right thing. -- STILL GRIEVING IN THE EAST

DEAR ABBY: The teaching profession is ruled by a strict ethical code. Failure to report any illegal activity, whether it involves your child or the children of your friends, and whether it occurs at your school or not, can result in the loss of your teaching certificate and expose you to liability.

As a high school teacher, I all too often see children destroyed by parents who choose to "handle things themselves," which typically means they handle nothing at all. Parents who "help" their children by protecting them from the consequences of their actions in truth do them harm. This world would be a far better place if there were more mothers like the writer of that letter. -- MEREDITH IN THOMASTON, GA.

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DEAR ABBY: My best friend, "Ted," and I recently met an attractive girl I'll call "Bridget." Ted was married and suggested I date Bridget. Within a few days, before I got up the nerve to ask her on a date, Ted broke up with his wife, moved in with me and started seeing Bridget.

This was awkward, but in addition, Bridget started making sexual advances toward me. Unfortunately, I didn't have the wisdom to keep away from her. Although we didn't have sex, I was closer to her than I should have been to my best friend's girl. Ted knows about it, and now ensures that Bridget and I are never alone together. He constantly worries about the situation, and it is interfering with his job.

I believe he wants to break up with her, but he's afraid I will date her. I agreed with his suggestion that we both stop talking to her, but they are still dating. She continues to flirt with me every time he leaves the room, and I am defenseless against a pretty woman. Bridget says she likes me, but she loves Ted. She clearly has some attachment issues. I would love to talk to her about them and help her.

I think Ted and I both have strong feelings for her. What should we do? Neither of us can resist when she cries or wants something. -- STUCK IN THE MIDDLE

DEAR STUCK: You are not helpless. Find your backbone, start using your head, and thank your lucky stars that Bridget "loves" Ted. If you were in his shoes, YOU would be the one constantly worried about who she was coming on to the minute your back was turned.

Bridget appears to use sex as a way of getting attention and validation. It's a problem that's beyond your expertise to fix -- and also mine. She may need professional counseling, or a self-help group for sexually compulsive people, once she finally admits she has a problem.

The best way I know to avoid temptation is to avoid tempting situations. In your case, that means spending as little time in Bridget's presence as possible.

DEAR ABBY: My mother-in-law, "Shirley," is a dear, sweet, caring and generous person. Therein lies the problem.

Each time she comes to visit, she brings things for the apartment. "Jasper" (her son) and I live in a small renovated loft. We both prefer a minimalist look, with just a few decorative items: a museum poster or something that an artist friend created.

Shirley loves craftsy, cutesy, cottage and country-style things. (To me, her home is cluttered with all of her "collections.") The things she brings us look completely out of place in our apartment.

I'm sure other people encounter this problem, too. What do we do with all the stuff she brings? And how do we convince her that, while she's entitled to her own preferences, they are not ours? -- HATES DUST-CATCHERS IN N. C.

DEAR HATES: Your problem is common. The time to nip it in the bud is now, before the situation becomes any more awkward than it already is. You and Jasper need to have a frank, kind, face-to-face chat with Shirley and let her know that you love her and appreciate her thoughtfulness -- but while some people regard empty space as a vacuum to be filled, others find it restful and serene. You and Jasper fall into the latter category. (Surely, she'll understand.) As for what to do with gifts already received, offer to give them back to her.