Researchers have been aware of the connection between a parent’s divorce and a child’s divorce for nearly a century, says Nicholas Wolfinger, a sociologist at the University of Utah. Further, as Wolfinger found after he started studying the subject in the 1990s, people with divorced parents are disproportionately likely to marry other people with divorced parents—and couples in which both partners are children of divorce are more likely to get divorced than couples in which just one person is.
Wolfinger says that researchers have some ideas about why divorce would be heritable. One theory is that many children of divorce don’t learn important lessons about commitment. “All couples fight,” Wolfinger explains. “If your parents stay together, they fight and then you realize these things aren’t fatal to a marriage. If you’re from a divorced family, you don’t learn that message, and [after fights] it seems like things are untenable. And so you bounce.”
One other (albeit minor) factor is genetics. By way of explanation, Wolfinger talked through a hypothetical generation-spanning chain of assholery: “Some people are jerks, and there is some component of being a jerk that appears to be purely genetic. So: You’re a jerk, you get married, you have a kid, you don't stay married—because you’re a dick—your kid inherits some of the genetic propensity to be a jerk. And so they get divorced.”
Though most studies have focused on divorce, some research has suggested that unmarried co-parents are more likely to break up if their parents also did. After a failed marriage or cohabiting relationship, fathers are likely to be less present in their kids’ lives than mothers are—according to census data, legal custody is granted to women in 83 percent of cases.
Linda Nielsen, a professor at Wake Forest University who studies father-daughter relationships, has found that the reduced presence of a father tends to harm girls’ educational prospects and physical health—as well as their marriages, which are more likely to end in divorce.
Nielsen says that fathers can help daughters build confidence in themselves, and that this confidence serves them well when selecting their partners. Girls who grow up “hungry for a better and deeper relationship with their fathers,” she says, often try to satiate that hunger “very quickly, with the first guys that come along.”
Very little research has been done on these issues as they pertain to lesbian daughters or same-sex parents, but other studies have found that sons are prone to conflict-heavy relationships in their teens when raised by a single mother (and children, of course, can have a hard time without a present mother as well).
Despite these challenges, the likelihood that children of divorce will go on to get a divorce themselves has diminished greatly over time. According to Wolfinger, in the early 1970s, married people with divorced parents were about twice as likely as married people from intact families to get a divorce; now, the former group is only about 1.2 times as likely to get a divorce as the latter group.