Among that number were, possibly, some whose deaths brought a modicum of relief. Maybe their lives contained more suffering than joy; maybe infirmity or dementia had upended family dynamics. So let’s set the staggering toll on the American family at about half a million active, involved, essential grandparents, give or take. Half a million elders who could have looked forward to years of acting as family fulcrum, their presence now abruptly truncated and never to be replaced.

The centrality of grandparents to family flourishing is nothing new. Throughout recorded history, involved grandparents, especially grandmothers, have helped promote the survival of their grandchildren, the stabilization of their communities, and even, according to the anthropological theory known as the grandmother hypothesis, the evolution of the species itself. While the very existence of postmenopausal women has been presented as an evolutionary mystery—Why would a species have evolved to spend up to one third of its typical life span unable to reproduce?—the grandmother hypothesis posits that they served an important adaptive role in our species’s early history. Without the distraction of babies of their own, according to this theory, older women in hunter-gatherer societies could focus on the welfare of the youngest generation, providing food and guidance for those children while their daughters were occupied with their next babies. The existence of grandmothers, especially maternal grandmothers, is thought to have helped early humans evolve a longer period of dependency during childhood, which in turn led to the development of a larger brain, a prolonged learning period and a more complex social life. And when having long-lived women in the family helped the youngest generation survive to reproductive age, Grandma was passing along her genes for longevity at the same time, thereby extending human life expectancy overall.