Money is the divorce predictor everyone’s heard of. A widely cited study of more than 4,500 couples using the National Survey of Families and Households, published by researchers Jeffrey Dew, Sonya Britt, and Sandra Huston in the journal Family Relations, found that how often couples argued about money was one of the strongest predictors of whether they’d eventually divorce. But newer research tracking couples specifically through their first years of marriage points to a quieter warning sign that shows up even earlier — and it isn’t about finances at all. It’s about the in-laws.
The study that isolated in-laws as their own risk factor
A 2021 study in Research in Human Development, led by Katherine Fiori of Adelphi University alongside Amy Rauer, Kira Birditt, Edna Brown, and Terri Orbuch — the sociologist behind the University of Michigan’s long-running Early Years of Marriage Project — followed 355 Black and White married couples for 16 years. The finding wasn’t simply that bad in-law relationships predicted divorce. It was subtler and, in a way, more troubling: when spouses disagreed with each other about how close they actually were to the wife’s family — one partner rating the relationship warm, the other rating it strained — that mismatch itself predicted divorce, independent of how the in-law relationship actually was on paper. Discord about the story you’re both telling yourselves about family, in other words, is its own separate risk.
Fresh 2026 data backs up the pattern across a longer stretch of marriage
A newer paper from the same research lineage, published in the Journal of Social and Personal Relationships in 2026 by M. Rosie Shrout, MiKaila Leonard, Rasheedah Adisa, Terri Orbuch, TeKisha Rice Wallace, Melissa Franks, and Arthur Aron, tracked 373 newlywed couples — 199 Black American and 174 White American — across all 16 years of the same Early Years of Marriage Project, controlling for income and education. The researchers found marital instability was consistently lower when spouses reported less family-related tension, and that having more family support and less family tension acted as a buffer specifically in the marriage’s roughest years — the ones where distress or emotional disconnection was already present. Family friction, in this data, doesn’t just coexist with a shaky marriage. It appears to make a shaky marriage measurably more likely to end.
Why in-law strain gets underestimated
Financial conflict is loud. It shows up in a single blown-up argument about a credit card statement, which is part of why the Dew, Britt, and Huston research found argument frequency about money such a strong signal — it’s a conflict couples can point to and count. In-law tension is slower and more diffuse: an offhand comment at a holiday dinner, a difference in how often each spouse wants to visit, a running low-grade sense that one partner’s family disapproves. It rarely produces one dramatic fight. It produces years of quiet, cumulative friction — which is exactly the kind of stress the Fiori and Shrout research suggests compounds unnoticed until it’s already reshaping the marriage.
Two predictors, two different timelines
None of this erases what the financial research found — arguing about money remains one of the most consistent predictors of divorce across the full span of a marriage. What the newer in-law research adds is timing: family discord and disagreement about family closeness appear to matter most, and most distinctly, in the first years, when couples are still negotiating whose family gets holidays, how much closeness is expected, and whose relatives get a vote in decisions. That’s precisely the window when financial conflict often hasn’t fully emerged yet, since many young couples are still merging finances, careers, or households.
The takeaway for the years that matter most
If you’re newly married and bracing for the fight you’ve been told to expect — the one about money — the data suggests you might also want to notice something quieter happening at your in-laws’ dinner table. It’s not that money doesn’t matter. It’s that in a marriage’s earliest years, the disagreement that predicts trouble might not be an argument at all. It might just be two people quietly telling themselves two different stories about how close they really are to each other’s families.
