But it was the moms whose color-coded home-school schedules were going viral. And 80 percent of single-parent households are headed by mothers, according to 2019 US Census Bureau data, who don’t have the luxury of dividing the work up. Women make up the majority of those who care for aging or sick family members. And it is undeniable, based on years of research, that women in opposite-sex couples simply do more of the domestic work and child-related planning — even in dual-earning couples and when the woman makes more money.

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“I think our normal dynamic is probably like a 65/35 — which is probably not uncommon,” said Sherrod, the lawyer. “And now it’s probably like an 80/20. I think part of it is — and I hate using generalizations — but women tend to be planners.” As soon as things got serious, she said, she went to school to get all her child’s work. “If someone else is doing it, it’s really easy not to,” she said.

Researchers call this the “second shift”: the idea that when a woman gets home at the end of the day, she must clock into her second, unpaid job — buying groceries, cooking, cleaning and doing dishes, plus “the invisible work” like planning, coordinating and anticipating needs, said Darby Saxbe, Ph.D., the director of the Center for the Changing Family at the University of Southern California.

But in a health crisis, that labor gap might become even more pronounced as moms tend to be the primary point of contact for family health issues.

Alina Salganicoff, Ph.D., the director of women’s health policy at Kaiser, noted that 77 percent of moms say they take their children for doctor appointments, compared to only 24 percent of dads, according to a 2017 survey. “This has been a consistent finding in this survey since 1999,” she said. The same 2017 survey found that of working parents, 40 percent of moms said they’d taken time off from work to stay at home with sick kids, compared to 10 percent of dads — and that more than half of those moms were not paid.

“I think there are a couple of things going on,” said Salganicoff. “One is that we have societal expectations and gender roles that have been very hard to change. So managing health — whether it’s kids’ health, a spouse’s health, or caregiving to parents and often to in-laws — these are responsibilities that are often shouldered by women.”