Dear Prudence,
My sister-in-law is infertile and makes it everyone’s problem. Every conversation is a minefield.  She gets upset if you talk about kids or you don’t talk about kids. She locked herself in the bathroom over a holiday meal because my sister mentioned she was pregnant again. She has screamed at me over my child-free stance and struggle to get sterilized because “how dare I waste my womb when there are other women in the world that want but can’t have babies.”
At Thanksgiving, my fiancé and I announced our engagement and he made a joke about getting used to the “stepkids” (I have some pet goats on my property). My sister-in-law decided to step in and lecture us that wasn’t funny and the wedding would be a waste since we weren’t planning to be a “real” family because we didn’t want kids. I snapped that what did that make her and my brother then? They sure as hell didn’t have any kids.
My sister-in-law predictably turned on the waterworks and locked herself in the guest bedroom while my fiancé and I beat an early retreat from my parents. My brother is furious with me. My parents think I should have just been silent because I know how she gets. My sister told me she wishes she could have witnessed the entire conversation because she is so sick of walking on eggshells around our sister-in-law. We have been sympathetic but after seven years of her drama, we are sick to death about it. My fiancé and I are going to his parents for Christmas but we did have a family vacation set up in the spring. What should we do?
—Final Straw