In Western culture, we tend to think of motherhood as “an instinct that comes as naturally to women as the sex drive does to men,” John Gillis writes in his book A World of Their Own Making. But in reality, parenting is a learned skill. And the traditional sources of knowledge are the women and men who have already raised a few whippersnappers themselves—the grandmas, grandpas, aunties, uncles, and nosy, helpful neighbors. Once the older generations disappeared from the home, so did their parenting knowledge and skills.