"Dad, how old were you when you lost your virginity?"
Yeah, the thought of me asking Dad about anything sexual completely squicks me out now -- I didn't even see the man naked until he was on his deathbed, for Chrissake, not once in my then 31 years of life -- but for some reason, it was important that he tell me. And before I go on, I need to point out here that Mother was a virgin when she got married at 27, and believe me, there's no question that she was.
Anyway, so I ask him, and he looked at me and told me it was none of my business. He wasn't shitty about it or anything, but that was that. It kind of makes me wonder now if he wasn't a virgin when they got married, and he told Mother he was, or if he was just that kind of squirrelly about talking sex with me.