DEAR ABBY: We have an annual weekend family reunion that includes family and significant others along with their children. Most of the children are adults now. One of them (my niece) was recently married and is asking if her new husband’s sister (and possibly her boyfriend) can come to the reunion.

We don’t have anyone other than immediate family attend, although we do have a special attendee this year. My brother-in-law’s mother is here from South America. She will be coming only for the day rather than the whole weekend. How do I politely refuse my niece’s request without hurting her feelings? — MORE OR MERRIER?

DEAR M. OR M.: An exception has already been made for your brother-in-law’s mother. I’m not sure you can refuse to include your niece’s new husband’s sister (and possibly her boyfriend) this time around without causing hurt feelings. Throw a few more hot dogs on the grill and cross your fingers that everyone will have a good time “just this once.”

Dear Abby is written by Abigail Van Buren, also known as Jeanne Phillips, and was founded by her mother, Pauline Phillips. Contact Dear Abby at www.DearAbby.com or P.O. Box 69440, Los Angeles, CA 90069.