DEAR ABBY: As a clinician specializing in geriatric mental health, I was concerned about your response to "Ambivalent in California" (Sept. 10). She asked whether to sever ties with her 85-year-old father after he molested his young granddaughter. Your advice to pursue treatment was on target, but the guilt trip you placed on Ambivalent for wanting to maintain a relationship with her father was cruel.

Given that his behavior did not manifest until an advanced age, it was almost certainly due to age-related changes consistent with emerging dementia. She will need to make sure that proper care is provided for her father and should be instrumental in accessing services and placement options that will guarantee he cannot victimize anyone else. (Elder services and her family physician can suggest appropriate referrals.)

She will also need to nurture and care for her daughter. Hopefully, with the assistance of a skilled professional, Grandpa's probable pathology can be delicately explained. It may help her healing process if she knows the cause of the behavior was illness.

Of course, it's important to protect the teenager from further harm, as she has already suffered enough. Fortunately, this can be accomplished without rejecting a weakened and elderly parent at a vulnerable time in his life. -- GERIATRIC PROFESSIONAL IN N.H.

DEAR GERIATRIC PROFESSIONAL: Thank you for offering a more empathetic insight than I offered. Other readers shared similar personal experiences that support your view. Read on:

DEAR ABBY: My grandfather was a dear man, a gentleman with whom I spent a great deal of time while growing up. We waded trout streams together, weeded gardens together, and he taught me to play cribbage. The warm memories go on and on.

But as an elderly man, nature caused him to take a turn. Mom telephoned us girls (now mothers ourselves) and warned us not to bring our daughters to visit. I was shocked at the idea that Grandpa had become a "dirty old man." But his kindness and gentleness were gone, as were his smile and the twinkle in his eye. He would have been horrified to realize what he had become.

Abby, you are right that "model fathers" do not molest their granddaughters. But elderly men sometimes, for some reason, can become unaware of their boundaries. And sometimes they become someone other than the person they were years ago. Please do not condemn them. -- BEEN THERE IN MICHIGAN

DEAR ABBY: My dad had dementia for a number of years before his death at 98. Dad, who had always been a prude about sex, began making inappropriate comments. It was caused by dementia. I wish I had been more understanding and patient with him.

I understand Ambivalent's love for her father and not wanting to cut him out of her life. She must explain to her daughter that her father is unable to think normally and clearly and visit him alone in his final years. -- STILL MISSING MY DAD

DEAR ABBY: My family experienced a similar situation. Although Dad never molested anyone, he did expose himself to my teenage nieces. He was diagnosed with dementia, and as a precaution, we no longer left him alone with our children. I am glad we got him the kind of help he needed. And I urge other families in this situation to find support groups. You are not alone. We lost Dad two years ago and miss him terribly. -- YOUNGEST DAUGHTER IN INDIANA

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DEAR ABBY: Several months ago, my 35-year-old sister met a man online. After corresponding (via telephone and e-mail) for about two weeks, she moved two states away to move in with him. She never saw a picture of him and had never met him in person before she moved to be with him.

This man -- I believe he's 45 -- now wants to communicate with my 14-year-old daughter. He tries to chat with her online and doesn't understand why I think it is inappropriate. He says he's "family" now, and I am being overprotective.

Abby, am I being overprotective of my daughter? I have never met or spoken to this man and feel he has no right to communicate with my daughter. Please help. -- LOSING IT IN MONROE, LA.

DEAR LOSING IT: It's your duty as a parent to protect your minor child from perceived danger. You sister's friend is acting like a pedophile and a stalker. He isn't "family," and objecting to your daughter being approached by a stranger is not being overprotective.

Since you don't know his background, contact the police department in the city in which he lives and ask if he has a record. Then Google him to find out if there's any information about him online. And, above all, warn your daughter not to trust him because, from your description, the man could be dangerous.

DEAR ABBY: I have been seeing a very nice man for about four months. He lives with his 23-year-old daughter.

He loves when I cook for him, and when he asks me to cook I do it because I enjoy it as a creative outlet. But every time I make a dish, his daughter comes along and adds things to it. I was making Sunday gravy, and she added something to that. Another time, I was making pasta primavera, and she poured a can of beans into it.

I am a very good cook, Abby. I do not need any help in the kitchen. How can I stop her from adding things to the meals I am cooking? -- FRUSTRATED IN FLORIDA

DEAR FRUSTRATED: The least confrontational way to accomplish it would be to cook for her father at YOUR house.

DEAR ABBY: Would you allow me to add to your letters sharing acts of kindness? My husband was deployed to Iraq for a year. Close to the time of his return, I went to some businesses in our community to ask if they would put welcome home messages in their windows or on their marquees. The responses I got were incredible!

An eye doctor even offered to give our family free eye exams and glasses/contacts if they were needed. A chiropractor offered to give my husband a free adjustment. I was overwhelmed with the support my family was given, as was my husband when, on the drive home, he saw message after message of support and welcome.

It was touching to see that the sacrifices he, and we as a family, made were appreciated by our community. -- THANKFUL AND INSPIRED, ROSWELL, GA.

DEAR THANKFUL AND INSPIRED: Your letter touched my heart, not only for the sacrifices your husband and family have made in the line of duty, but also because of the spirit displayed by the members of the business community in your city. We all owe a debt of gratitude to the brave young men and women who serve in our armed forces, and it is one that should never be forgotten.

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DEAR ABBY: My husband, "Cal," and I have decided to have Thanksgiving at our house this year. The last three years we have gone to my sister-in-law's house. When I told my father-in-law our decision, he yelled at me and walked out of my home. After that he called Cal and screamed at him, saying that we are being disrespectful to him.

The guys usually hunt over that holiday weekend. By celebrating Thanksgiving here, my father-in-law says we are depriving him of four days he could be hunting with my husband. I suggested that they do it here, but he insisted there is no good game around here. After another round of yelling, my father-in-law hung up on Cal.

I don't understand what the problem is. We thought it would be nice to finally have Thanksgiving dinner at our house. I don't know what to say to my father-in-law now. I feel very hurt. It's causing a lot of stress, as if the holidays are not already stressful enough. What should I do about this? -- STRESSED OVER THE HOLIDAYS

DEAR STRESSED: Your father-in-law behaved like a rude child. It wouldn't hurt him to let the wild animal population build itself up again for a year. Please don't take what he said personally.

Be sure your father-in-law knows exactly when Thanksgiving dinner will be served. Set a place for him, but don't count on him showing up. If he doesn't, you will know where his priorities lie. However, if he does come and sulk, ignore the petulance and go on with the party.

DEAR ABBY: My brother "Wilbur" is supposedly bipolar and hasn't held a job for more than six months at a crack. He is going to be 48 years old. In between jobs, he ran to our parents for financial help. When Dad was around, he could control it somewhat. But Dad is gone now, so Mom is giving all this money to Wilbur.

Mom was recently diagnosed with Alzheimer's, so how do we stop this nonsense? Wilbur won't quit demanding money. I think Mom is afraid not to give it to him because she thinks he'll go wacko. Wilbur doesn't have a permanent address because he's in and out of homeless shelters, so we can't get a restraining order. Please help, because this is stressing our family out. Mom needs to know that she owes Wilbur nothing, and it's OK to turn him out of her home and cut off the funding.

I know a power of attorney will do the trick, but how do you make a person realize that her son is a con artist and is just abusing her? For 27 years I have argued with Mom over all that she has given Wilbur. In her final years, I'd like to enjoy our time together and not fight. By the way, my sister and two other brothers feel the same. Any ideas? -- HAD IT IN THE U.S.A.

DEAR HAD IT: You have my sympathy. The money your mother is doling out is a Band-Aid on a broken arm; it isn't solving your brother's basic problem, which is the need to be treated and medicated.

Your mother is ill, and she isn't going to get better. You will get nowhere trying to argue with her. Therefore, it is time for you and your siblings to consult a lawyer about a power of attorney for her financial matters, and a power of attorney for health care if she doesn't already have one.

By the way, if your mother is being "bled" for money, it could be considered elder abuse. An attorney, as well as your state's Area Agency on Aging (it's listed in your phone directory), can help you put a stop to it.