Bedtime Questions

Our kids have been asking some of the toughest questions at bedtime lately. Some are related to movies watched, some are from books, some are related to people they know, ect.: "Why do people get divorced", "What's a hernia", "What happens with puberty". Since I am usually tending to Abigail, they sure do have Ian spinning in circles. I've heard this is a time when kids can really open up. I do not want to be squelching that, but also do not want support a convenient way for them to delay bedtime either.