Sonia Salari, a sociologist at the University of Utah, regularly teaches a course in family studies—and when she does, she asks her students the same question: “Who here is closest to their maternal grandmother, out of all their grandparents?” Reliably, the majority of hands shoot up. Next, she asks, “Who is closest to their maternal grandfather?” Then she asks about the paternal grandmother, and then the paternal grandfather. With each subsequent question, the number of hands dwindles. “It’s just always the same,” she told me.
Salari’s survey is a perfect segue into her lesson on what researchers call the “matrilineal advantage”: People tend to rate relationships with their mother’s side of the family more favorably. In one study, children reported having stronger bonds with their maternal grandparents, particularly with their maternal grandmothers; the authors noted that the finding seemed especially significant given that kids are more likely to live near their paternal grandparents. Research has also found that grandparents tend to feel especially connected to their daughters’ children. When participants in one study rated how likely they would be to save a particular cousin hypothetically trapped in a burning building—admittedly an intense survey question—the majority said they would behave most altruistically toward their maternal aunt’s children, followed by their maternal uncle’s, then their paternal aunt’s, and finally their paternal uncle’s.
Although the matrilineal advantage doesn’t apply to every culture and person, it’s been well documented, especially in the U.S. and Europe. So why is this the case?
One key factor may be that women are more likely to fulfill kinkeeping roles, meaning they take on the often invisible labor of maintaining their family’s closeness. That might include calling and visiting relatives, remembering birthdays, sending holiday cards, and organizing vacations and events—along with being sensitive to everyone’s needs when those events happen. Kathrin Boerner, a gerontologist who studies family caregiving at the University of Massachusetts Boston, told me that kinkeeping isn’t just about, say, hosting dinners. “When the dinner happens,” she said, part of the challenge is “how do I set it up so that people actually want to be in the same room together?” When the researchers behind a 2017 study placed a call for participants who identified as kinkeepers, 91 percent of their subjects were women. Another, published in 2010, examined three-generation families—and found that mothers were responsible for the large majority of caregiving and communication, followed not by fathers but by maternal grandmothers.
Given that women are more likely to maintain family networks, they’re also likely to be at the center of those networks. But the “matrilineal advantage” doesn’t just apply to the women who do the kinkeeping and caregiving—it can extend to their whole side of the family. Think about it this way: Mothers tend to do the majority of the child care and housework; one study found that women are more likely to take on the brunt of those duties even when they earn more than their spouse does. They’re also more likely to receive babysitting help from (and simply spend time with) their own family from their husband’s family. Eventually, then, tighter relationships can form between kids and the maternal relatives they’ve grown up around, and that can last into adulthood.
Of course, the division of labor is not so lopsided in every family—and notably, researchers have found the matrilineal advantage to be weaker in European countries where stereotypical gender roles aren’t as pronounced. But in many countries, even as equality in the workplace has advanced, there has been significantly less progress at home: Mom is still commonly the chief-executive parent. The irony is that the same patriarchal system that has historically left women with disproportionate child-care responsibility has also given many of them an invaluable closeness with family.
Lacking those tight ties can be a real loss for fathers and their relatives. In the average month in 2015, 300,000 women took parental leave compared with 22,000 men—but when men do take paternity leave, the majority of them are glad they did. Research suggests that fathers who take leave are more engaged with their kids throughout the first years of their lives. Plenty of people have argued for equitable parental leave on the grounds that it could get fathers more involved from the start in child-rearing. But it wouldn’t just benefit dads and their kids; it could strengthen children’s bonds with their whole extended family.
Granted, the matrilineal advantage can be a vicious cycle: When so many adults feel distant from their father’s side, that can reinforce the association between maternal relatives and family in general—and prevent people from assuming that paternal kin should be just as involved. But if more dads were engaged in parenting and kinkeeping in the first place, they might need to rely on their relatives for help; the more the paternal side is involved, the more the expectations for them might shift.
There’s no reason we shouldn’t give fathers the chance to start that chain reaction. “When men are in roles of caregiving, there is no evidence to suggest they’re not going to do a good job,” Salari told me. “They’re just as capable of it.” And if they’re pulled into the fold, they might bring the rest of their family with them.