DEAR ABBY: My son, who is 5, has a rare spinal cord injury from birth. He can crawl, but he does not walk well. We have spent many months and a lot of money ensuring he is getting the best physical therapy and medical care possible for his condition, and we adhere closely to the medical advice of these experts.

My mother, who lives 2,000 miles away, loves my son and wants to spend time with him. However, whenever we visit, she obsesses over the fact that my son can’t walk well. I have reminded her not to fixate on his disability and to just enjoy time with him, which is what my son wants. But during this last visit, she told him “big boys walk, they don’t crawl.” And, “Try harder to walk.”

My son has tearfully asked me twice if he can still be a big boy and crawl. (He also uses a wheelchair). I’m fed up with my mother and would prefer to keep her away from my son, but I don’t want to create a dramatic familial rift. Advice? — GOOD MOM IN MONTANA

DEAR MOM: It is your duty as a mother to protect your son from harm. Tell your “helpful” mother that if she says anything again to shame him, it will be the last time she sees him. The person who creates the familial rift won’t be you, it will be your incredibly ignorant and insensitive mother.

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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.