Help! My Sister-in-Law Has Latched on to Our Healthy Hobby. Her Expectations of Us Are Outrageous.

Dear Prudence July 20, 20266:00 AM Photo illustration by Slate. Photo by Getty Images Plus. Our advice columnists have heard it all over the years—so we’re diving into the Dear Prudence archives to share classic letters with our readers. Submit your own questions to Prudie here. Dear Prudence, My husband and I have been competitive distance runners for the past two years. We love competing for personal bests in formal timed races we enter, and it’s been a great activity we can do together that has helped us stay healthy. Then a few months ago, my sister-in-law took a sudden interest in running and has wedged herself into our running habit. We assumed that her interest would go the way of her previous fitness interests and fizzle out over time. (She went to Crossfit five times a week for tw