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Q. When Mom wears her muummuu: My husband and I have lived together for five years. We live four hours away from my mom, and she visits frequently. Most of the visits go well, except during the mornings. My mom loves muumuus and flowy nightgowns. She does not like underwear. However someone wants to sleep is their business. But she frequently sits so that she’s bare-bummed on the furniture, or puts her legs on the ottoman in such a way that you can clearly see where the sun doesn’t shine. How do I institute an underwear-and-nightgown policy when she visits?

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A: Congratulations on having a very reasonable underwear policy! It’s a perfectly sound request not to want to have to clean one’s couch after someone sits on it bare-assed, and to draw the line with regard to slightly relaxed dressing standards around the house without getting flashed by your mother. (We had a somewhat related letter last week, about a family member sitting down at the breakfast table in a shirt and no bra, and I had different advice then. I think going clothed-but-braless is a decent standard of at-home relaxation but that going bottomless crosses a line. Unless everyone in the family is a nudist! But even then, I think most nudists carry around a little towel to sit on, don’t they?)

There’s no special trick to it. You just have to be willing to say the word underwear to your mother: “Mom, I love our visits so much. I’m a little embarrassed to have to say this, but we need you to wear underwear out in the common spaces so we don’t have to deal with bare bums on the couch or accidentally getting flashed. Thank you so much.” Say this in a tone that’s both chipper and yet capable of communicating, “I sure hope I never have to ask you this again.”