DEAR ABBY: Have you ever heard the saying, "A daughter is a daughter all of her life, but a son is a son 'til he takes a wife"? Our son and his family have never spent a single Christmas Eve or Christmas Day with us during the entire 17 years they have been married. A Thanksgiving with them is very rare.

They live an hour away. We and his in-laws live in the same small town, but they spend every holiday at the in-laws'. Their children have no memories of us on the holidays. When I talked about it with our friends, they said they have the same problem. All of their sons go to their daughter-in-laws' parents', too.

With the holidays coming up, I hope you may have something to say about this. When we spoke to our son about it, it just caused bad feelings. -- SAME PROBLEM IN MINNESOTA

DEAR PROBLEM: My heart goes out to you and other parents who experience this. However, there is nothing I can do to change the behavior of adult children, as regrettable as it may be. The best advice I can offer is for you -- and your friends -- to spend the holidays doing things that you enjoy. Take a trip, gather with these friends and celebrate. It would be a lot healthier than sitting around brooding about something none of you can control.

P.S. It's regrettable that although you live in the same community as the in-laws, you have not been asked to join them for a holiday meal at their table. After all, marriage is supposed to unite families, not divide them.

DEAR ABBY: I'm a woman in my 50s and will be going to my high school reunion in a few months. I recently reconnected with one of my high school teachers, whom I greatly admired. (OK, I'll admit I had a schoolgirl crush on him.)

He is 10 years older, and we had a friendly relationship "back in the day" with extracurricular school activities (he was a sponsor) and even some outside socializing (dances and such), though there were no lines crossed as far as impropriety. We were both engaged to other people (who both happened to live a good distance away) at the time, so there was no thought of a romantic relationship.

Fast-forward 40-odd years. We are both single (I'm divorced; he never married). We have been emailing back and forth for a couple of months and making plans to get together at the reunion -- maybe before. We have discussed a lot of things, but he never mentions dating or his former fiancee, so I sometimes wonder if he might be gay.

I have two questions: (1) Would it still be crossing a line if we started a romantic relationship because I was once his student? (He's long retired.) (2) How do you ask a man or find out if he's gay before you embarrass yourself by trying to start a romance? -- TORN IN THE SOUTH

DEAR TORN: It would not be crossing a line if you and your former teacher were to start a romantic relationship at this point in your lives. However, before you embark on that campaign, it is important that you understand why he has been single all these years. A way to do that without embarrassing yourself would be to pay him a compliment by saying, "Why is it that such a great guy like you has never married?" Then listen.

DEAR ABBY: My sister has been having an affair with a married man. When I asked if he was going to leave his wife, she said no, and it was fine with her. She claims his wife is fat and that they have a son with severe disabilities, and she (my sister) wouldn't want the responsibility of that, even though I'm sure the boy would stay with his mother.

She refers to him as her "honey," and he buys her things. (She has always been materialistic.) She stays in contact with him constantly on her iPad and says how much he loves her.

I would want to be open and have everyone get to know about my honey instead of sneaking around. When I say I don't believe he loves her, she gets mad and accuses me of being jealous. I also told her that if I loved someone, I'd want to be with him and not communicate via email. Gifts wouldn't make up for the person not being with me, especially if I claimed to love him.

I was in a relationship with a married man once, but I wasn't happy about it and ended it. Am I off base because I feel the way I do? -- SNEAKING AROUND IN MAINE

DEAR SNEAKING: You're not off base. But you're also not your sister. The two of you appear to have very different values. While you want a full relationship, the "crumbs" and goodies she's getting from her honey may be enough for her, and she may regard their stolen moments as exciting. If she were hoping for more than the status quo, I would say she's wasting her time. But she seems to know the score.

DEAR ABBY: I know three people who have cancer. One is terminal, one is probably terminal and the other is possibly terminal. The second and third individuals I've known for a long time. The terminal person, however, is a social acquaintance -- someone I met through a close friend.

Over the last two years we have socialized a half-dozen times, but we've never had an extended conversation, and I don't especially like her. As her condition has worsened, she has withdrawn from most socializing. I receive updates from my friend, who takes her to appointments, shopping, etc. when she can't drive herself or when she feels the woman needs company. Officially, I don't know anything. But I was told her oncologist has informed her she's got six months.

My question is: Should I contact her? I'll feel like an idiot and like I'm invading her privacy if I do, yet somehow guilty if I don't. The only thing I would say to her is that I'm sorry this has happened to her. My gut tells me I should keep quiet, but my guilt is getting in the way. -- FRIEND OF A FRIEND IN NEW YORK

DEAR FRIEND: I assume you know as much about this woman as you do because your good friend is confiding in you. If you don't know anything "officially," I assume your friend was sworn to secrecy and chose to tell you because she receives emotional support from you. I see nothing to be gained by inserting yourself at this point, and you should not feel guilty for keeping your distance. Listen to your gut.

DEAR ABBY: Holidays can be stressful and even dangerous for pets. Here are some things pet owners can do to make them less so for their four-legged companions:

1. Feed, walk or play with them before the party, then take them to a quiet room with water and a nice treat. With a cat, make sure they have their litter box as well.

2. If you're traveling, make sure your pet is properly restrained in your car with a seat belt harness or a secured carry crate. If you can't take your pet along, board your pet or use a reliable pet sitter.

3. Remember that "people food" usually isn't safe for Fido or Fluffy. Chocolate, alcohol, eggnog (dairy) and other items can be toxic to your pet. DO have appropriate treats on hand.

4. Don't leave dogs outside, especially if it gets cold. Bring them inside.

5. If you have cats that go outside, consider bringing them in or providing a nice, warm box for them to curl up in at night.

6. Christmas trees are pure temptation for your cat, with dangling items to play with and an opportunity to climb. Be sure your tree is securely anchored. Consider leaving the tinsel off your tree, and placing your ornaments where the cats cannot knock them off.

7. Electrical cords look like things to chew and can shock your pet. Cover them with special cord covers or use chew-deterrent sprays.

8. Christmas wrapping paper, ribbon and other items can choke your pet. So dispose of waste from opening presents right away.

I hope these tips will help everyone have a safe and great holiday season. -- ANIMAL LOVER IN PENNSYLVANIA

DEAR ANIMAL LOVER: And I hope my readers will take to heart what you have written because your suggestions are important. Thank you for your letter.

DEAR ABBY: My uncle who has Alzheimer's has declined rapidly. Prior to his decline, I bought 30 greeting cards every month and made sure to mail one to him each day. I live in Florida, and he lives in Kentucky.

I received much satisfaction and joy with every post I sent. My mother would open the cards and tape them to the outside of the door of his room. His neighbors would pause and read them as they passed by, and he used the montage of seasonal greetings as a way to recognize his door.

My uncle is no longer cognizant or coherent, and my mother has told me to stop sending the cards. Abby, I need this activity in my life. How can I find another person who would welcome a greeting card? I am semi-paralyzed and confined to a wheelchair. I have no interest in meeting, visiting or even talking to the recipient; I just want to send greeting cards. Suggestions? -- LOVES SENDING SMILES

DEAR LOVES: It's time to find another outlet for your caring and compassion. Contact the eldercare facilities in your community, speak to the directors and ask if one (or more) of the residents might enjoy receiving your seasonal greetings. I'm betting the answer will be yes.