DD1, 7, has been asking for a bit more detail recently on how babies are made. She knows about periods and pregnancy - I don't know if she's ready for the full details but I think I need to give her more than "an egg and a little swimmer". I'd like to stop short of explaining what sex is though, I feel like maybe a year or 18 months is early enough for that?
Are there any books on this that anyone would recommend? And experiences? Do you think I'm about right on my timing?