Q.Should I say something about my brother-in-law's treatment of his stepdaughters, 10 and 12?

I mostly see this family on holidays, where he acts in a super-controlling way with the girls and belittles them every moment they are together.

For instance, he once made the younger one take off her coat even though it was freezing and she was cold. He forces them to eat everything on their plate, which creates a constant battle at mealtime. And when a relative asked one of the girls to do her impression of an actor, he sarcastically told her, "Go ahead. You always want to be the center of attention, so do it."

It is hard to express how mean he sounds when talking to my nieces but he is much nicer to his son -- a high school student -- and treats him like his buddy.

He is also very loving to us and to the rest of the family, which must make my nieces think that they are horrible people.

Although he has been married to my husband's sister for five years -- the biological father is out of the picture, thank goodness -- she never objects to his discipline of the girls. Perhaps she complains when no one is around but if so, her words have no effect on him. Should I say something to her or to my brother-in law? Or do they just have a different parenting style than we do? I also wonder if he acts this way because he was once an alcoholic.

I don't think my brother-in-law is a bad person and I know he thinks he is doing the right thing for his stepdaughters, but how can I help these girls?

A.Before you do anything, be sure that your nieces are as bothered by their stepfather's discipline as you are.

Watch how the girls act when he sounds off. Do they cringe? Do they look hurt or angry? Embarrassed or humiliated?

While many children would be quite upset by such over-the-top behavior, others are surprisingly resilient and your nieces may be, too.

They also may accept their stepfather's behavior because they think his intentions are kinder than his actions or because -- like most children -- they instinctively know that each parent disciplines in a slightly different way.

Words that would be devastating to hear from their mother may not bother them much from their stepfather, but that's only true if the children know that their parents will treat them the same way, day after day, and love them completely, no matter what.

Even if your nieces don't seem to mind your brother-in-law's behavior, they need you to intervene because the same verbal abuse that they tolerate in their middle years could destroy their self-esteem in adolescence.

Talk with him -- kindly, respectfully and in private -- and ask if he knows how scary he sounds when he corrects his stepdaughters and how much more kindly he treats his own son. If he is as loving as you say, he will probably be shocked to hear what you think and may be somewhat willing to change his ways.

If he must have the girls eat everything on their plates, for instance -- a truly outdated idea -- suggest that he let them serve themselves, taking a little of everything. Since children know how hungry they are and which textures, flavors and spices they like, they probably will eat most of their meal and if they aren't hungry enough to do that, they aren't hungry enough for dessert.

To eat, or not to eat, should never be an issue at mealtime, or any other time. That just encourages a child to eat too much -- or too little -- in the coming years.

If your brother-in-law can't stomach your criticism, you could quietly videotape him when he disciplines the girls unfairly, as part of your annual holiday tape. Seeing himself in action may make him change faster than anything else.

Without counseling, however, he will still be a controlling person and perhaps an abusive one, not because of his past alcoholism, but because he may have been verbally abused when he was young.

Even with therapy he may not change the way he deals with the girls in their middle years. As Ellen Galinsky points out so well in her classic book "The Six Stages of Parenthood" (Addison Wesley, $21), no one is an equally good parent at every stage of a child's life, from pregnancy to adulthood.

Both your brother- and sister-in-law could also profit from reading the new book "Strengthening Your Stepfamily" by Elizabeth Einstein and Linda Albert (Impact, $17.95). It's packed with insightful information that both of them can use.

Questions? Send them to advice@margueritekelly.com or to Box 15310, Washington, D.C. 20003.