I second JB Dad's recommendation of It's So Amazing. It goes through anatomy, the sperm-meets-egg bit, fetal development, birth, etc., but totally glosses over how *exactly* the sperm gets into the egg's neighborhood, so to speak. There is one drawing, IIRC, of a man and woman in bed under a blanket, and that's it.
Another aspect of the book that I really appreciated was its openness to *all* kinds of love, and pointing out that that kind of relationship is different from a sibling relationship or friendship, etc. The illustrations also include people from all walks of life, not just healthy white beautiful middle-class heterosexual Christians.
