Weakened family ties have all sorts of consequences for parents. They affect, for instance, women’s workforce attachment: married women with kids in elementary school or younger are 4 to 10 percent more likely to work if they live near their mothers or mothers-in-law. The social lives of parents are also affected: without the most reliable, most psychologically reassuring, and (above all) most affordable form of babysitting—namely, grandparents—a simple evening out with one’s spouse is a much harder sell.

