My inquisitive seven year old daughter (R*) has discovered sex - thanks to a book and her new found reading skills. From the "Usborne Pocket Scientist", I quote page 58 with the heading "How does a baby start?":
"A baby starts to grow when an egg and sperm meet and join together. They do this inside the mother's body. The way the sperm get to the egg is through the mother's vagina. The mother and father cuddle each other very close. The father's penis gets stiffer and fits comfortably inside the mother's vagina. This is called making love or having sex".
R* decided to mention this the other day in the car while we were driving off to buy some groceries. Our reaction was just "Ummmmm. Yes, yes. That's right." while exchanging bewildered glances. R* then confesses that she has been reading and re-reading this section on "Where do babies come from" VERY carefully.
On subsequent inspection, the book does seem to be quite thorough and well illustrated. Time to hide our old copy of "The Joy of Sex"! Glad she thinks the idea is rather gross.