Dear Grandparenting: My daughter Sally’s life is fast going from bad to worse because of my grandson Tyler. When Tyler was younger and had temper tantrums, I didn’t give it much thought, because many children go through that difficult period around age 2. But Tyler never outgrew the “terrible twos.”

Tyler is now 7. Sally seldom takes him anywhere, because he could erupt at any time. When he plays with friends, fights usually break out. The word that maybe best describes Tyler is “defiant.” Sometimes he gets really aggressive when he’s angry, and he says and does mean things.

I’m worried about how to control Tyler and scared about Sally’s marriage and her mental health. She’s become isolated and full of guilt and shame about Tyler. Sally says people assume she’s a terrible mother because of Tyler’s behavior.

Her husband, Jim, spends less and less time at home. Jim’s a big believer in physically disciplining children who act up. But that doesn’t work with Tyler. It just provokes him. But talking to Tyler definitely doesn’t work, and threats and punishment don’t work either. I hate feeling so helpless. Is there any way out? — “Helpless,” Chestertown, Md.

Dear Helpless: This cries out for professional counseling and intervention. Diagnosing the underlying cause of antisocial behavior is best left to child psychologists and developmental pediatricians.

Some experts, like Philip and Nancy Hall, say the first order of business is to deal with stressors impairing the parents. Sally may think she’s fighting this all alone, but according to the American Psychiatric Association, defiant “conduct disorders” occur in six to 10 percent of the population.

Grand Remark

“If things get better with age, than I’m approaching magnificent.” — Overheard by Fran Olsen of Boston while visiting relatives in Laconia, N.H.

(Dee and Tom, married more than 50 years, have eight grandchildren. Together with Key, they welcome questions, suggestions and Grand Remarks of the Week. Send to P.O. Box 27454, Towson, MD, 21285.)