An excellent book for adults to share with children who are curious about their prenatal lives. Pringle (Naming the Cat, p. 1035, etc.), addressing listeners directly, begins with fertilization (the mechanics of conception are deliberately left beyond the scope of this book), details the various developmental stages of the embryo and fetus, and ends with birth. Soft, discreet pencil drawings on pink, blue, and lavender pastel backgrounds show how a baby grows from a cluster of undifferentiated cells into a newborn being welcomed by happy parents and big sister. There is just enough information, in text and illustrations, for preschoolers; Pringle also offers thoughtful suggestions for personalizing the explanation but cautions against ``overtelling.'' Admirably restrained and formal, but not without warmth. (further reading) (Picture book/nonfiction. 4-8)