One day, a little over a year ago, Pippi and I were talking about the coming arrival of Bardo. Pippi asked all kinds of questions about what would happen, etc. I basically ended up describing child birth to my four-year-old. Then she insistently asked me how Bardo got in my belly anyway. I was completely caught off-guard. I can't remember exactly what I said, but I was NOT ready to answer the question, and I deflected it somehow so I could think about how I was going to handle it.
A few days later I happed upon It's Not the Stork by Robie H. Harris at the library while Pippi was at story time. It was an answer to a prayer. I left the book out where Pippi would find it. She picked it up and immediately brought it to me. She LOVES the book, and just asked me if we could get it again when she saw me blogging about it. If you have a child between the ages of 4 and 7, this book is a great way to answer those important questions. You might want to check it out from the library, though, so that you don't have to talk about sex every night with your preschooler. This was THE book for over a month. And seriously, the pictures just make me laugh.
Note: Harris has a different book for older kids that gets rave reviews, as well.