Dear Prudence,
I am a recent college graduate. I had a tough time in high school; my mother died in freshman year, and my father became pretty much absent. Throughout those four years, I became very close with my sister, “Melissa.” She’s a couple of years older than me, and we became inseparable after our mom’s death. Now, there’s just one problem.
Melissa is engaged to a man about 20 years older than her, “Tanner.” (I don’t have a problem with the age gap at all; he’s pretty great.) Tanner has an adult daughter, though, “Analise,” from his previous marriage. She’s my age. As Melissa and Tanner prepare for their wedding, Analise and I have begun to hang out a lot more. We live near each other, and we meet for coffee very often. To be honest, I have feelings for her, and I think she might have feelings for me. I have no idea if Melissa (or Tanner) would feel upset if I were to date her! I want to ask her out so badly, but I’m consumed by the idea that if we do get serious and get married, my older sister would become my mother-in-law! What should I do?