Dear Annie: I am in my mid-30s and have a best friend the same age. I have known "Kyle" and his wife for a number of years, and we are involved in many activities together. I also have a younger sister, "Janice," age 23.

Last year, Janice met Kyle when she joined our gym. When a group of us planned to attend a football game, Kyle asked Janice to come along. Over the last few months, Kyle has involved Janice more and more in things my friends and I do together. Sometimes his wife comes along, sometimes not.

Recently, Kyle has indicated that things are bumpy in his marriage, and I can't help but worry that he has been laying the groundwork to start up with my sister. Maybe his motives are purely friendly, but if he's up to no good, do I have a right to feel betrayed if my best friend and sister get together? I can only envision this damaging both relationships. What should I do? — Big Brother

Dear Brother: The person who should feel betrayed is Kyle's wife. If you are concerned for Janice's emotional health, you should make her aware of your reservations regarding Kyle. You also can encourage Kyle to get into counseling and not pursue other relationships while he is still married. However, Janice is an adult and responsible for her own decisions — good or bad. If she chooses to be with Kyle, there isn't much you can do.

Dear Annie: I'm in middle school and good friends with "Amanda." Last week, she invited me for a sleepover. As soon as I entered her house, I started coughing. Her mother and older brother smoke a lot. No windows were open and the whole house reeked of cigarettes. When I left, my head hurt and my clothes and pillow smelled of smoke.

I really like Amanda and she is always welcome in my house. But what should I do if she asks me to come over to her place again? I don't want to hurt her feelings, but I can't stay there. — Can't Stand the Smoke

Dear Can't Stand: And you shouldn't have to. Amanda's exposure to secondhand smoke doesn't bother her because she's used to it, but it's very unhealthy. It's OK to give her a polite version of the truth — that you are sensitive to smoke and get headaches when you are in a house where there are smokers. Say that you're sorry you can't stay at her place again, but she is welcome at yours. In fact, invite her for a sleepover soon.

Dear Annie: You've printed several letters about the stress of living with an elder parent. After five years, my husband and I had to ask my mother-in-law to leave our home.

My mother-in-law is a wonderful person and we always got along well, so it surprised me that the arrangement didn't work out. One of the greatest stressors was the lack of privacy. And no matter how kind, elder parents often treat the adult son or daughter as a child, offering unwelcome criticisms. The elder parent sees these as helpful, loving gestures, but it builds resentment. And without meaning to, an elder parent can become very demanding — wanting to be driven to the mall to shop, etc. For a busy mom and dad who work, drive carpools and run errands all day, it is simply another task on our long list.

My husband's siblings, who were not involved in Mom's care, didn't understand the stress. They also assumed we were after Mom's money, since she provided financial assistance with the living situation.

It has been almost three years since my mother-in-law left. She is living on her own and doing well. My husband and I had to be treated for depression and are now estranged from the extended family. My advice to anyone thinking about having an elder parent move in is to consider other options first. — Meant Well