Mommunes, triads, and the changing household

Not-so-nuclear families are the norm now. So why isn’t there more support for them?

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Key takeaways

  • Nuclear families in the US make up only about a quarter of all family types now.
  • Economic and social forces are making other kinds of households, such as "mommunes," more common.
  • People in these living arrangements need unique support and guidance.

"Traditional" families are now the minority. US Census data from 2021 showed that married, heterosexual couples with children under 18 make up only 27% of all US family groups—and even less of all household types.1

"The concept of a family has been changing over the past few decades," says futurist Jacob Morgan, author of The Future Leader: 9 Skills and Mindsets to Succeed in the Next Decade. But what's going on now, including the pandemic, child care shortages, and inflation, may be accelerating change. And resources, advice, and even tax law for burgeoning family and household types aren't keeping pace.

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Nontraditional household types are gaining popularity

Along with a drop in the share of nuclear families, more people are living alone, says Morgan. According to US Census data, 28% of all households in 2021 had just 1 person; in 1960, they accounted for only 13%. That rise is mostly because people are putting off or skipping marriage and having kids, according to the Pew Research Center.2 Living longer also plays a role.

But that's not the only new trend that's emerged. More people who didn't previously tend to live together are cohabiting now, such as single-parent families. They've gone from 4% of all households in 1960 to 9% in 2020.3 In the face of high housing and child care costs—or a lack of child care altogether—some single moms are moving in together. "The cost of living drops when you have more adults in one household because you can share expenses," says Isabel Sawhill, Senior Fellow at the Brookings Institute.

Morgan says these "mommunes" have social and emotional perks too. "They benefit moms who feel isolated raising kids on their own and who find it helpful to be around other parents who are going through the same things," he says.

The village mentality—and cost-sharing benefits—also shows up in the rise of multigeneration households. The number of people living in those homes quadrupled between 1971 to 2021, now making up 18% of the population according to the Pew Research Center.4

"Young adults are moving back in with their parents," says Adriana Reyes, PhD, assistant professor of policy analysis and management at Cornell University, who studies the financial and health consequences of living arrangements. "Housing prices have soared, so buying a house has become unattainable for young people." Plus, more years of schooling and putting off marriage means young people wait longer to start their own households.

The arrangement can have benefits for the older generation too, says Reyes. "When young adults live with their aging parents, they might be more available for caregiving because they are already living there and feel closeness or obligation to pay back the help they've gotten," Reyes adds.

Another nontraditional household you may be hearing more about: triads, or 3 people in a romantic relationship living together. "During COVID, a lot of people in the polyamory community moved in together to form their own pod and limit exposure to others," says Jennifer Schneider, a licensed clinical social worker and therapist who specializes in the polyamorous community. "It was easier for them to see each other and helped them cope better with the pandemic."

The Census doesn't ask specifically about polyamorous groupings, so it's hard to know whether they are becoming more prevalent. But, says Schneider, "social media has made it seem more common."

Nontraditional families have unique considerations

Non-nuclear families face challenges in the current financial system. Single parents often have slashed income or assets after divorce, and may have trouble making ends meet. They have the added worry of child care if they get sick or die. That's why it's critical for single parents to establish an emergency fund, with enough to cover 3 to 6 months of necessary expenses. Disability and life insurance could be helpful too.

As for triads, in most of the country, they can't take advantage of domestic partner or tax benefits, or share guardianship of a child. And while there's no legal limit on the amount of people who can be on a mortgage, triads can have a tough time getting a loan because of lenders' rules or biases. There are, however, polyamory-friendly banks.

Still, there are risks to consider before going in on a mortgage with someone who isn't your legal spouse. For instance, if they default on their portion, it can drag down your credit score. To protect yourself, you could create a cohabitation agreement, like a prenup, before you buy a place together. It would include how to divvy up property if you split.

Even in the case of multigenerational households, members should discuss how bills will be split. A young person who cannot afford rent could still contribute to the household—financially or otherwise, says Reyes.

The No. 1 rule for anyone living under the same roof? Communicate early and often. "When there is a merging of finances, people need to have structured discussions," says Schneider. "Who will be the primary breadwinner? Does a full-time student have to contribute financially? What about a full-time parent?"

The Fidelity Center for Family Engagement (FCFE) helps advisors and families navigate complex emotional and family dynamics around money. In a recent white paper, Best Practices for Navigating the Decade of Generational Wealth,5 FCFE's Timothy Habbershon, EdD, and Tobias Donath identify "engaging the modern family and complex planning considerations" as a priority for financial pros in the coming decade. "Currently, our industry is largely organized around a traditional view of client families as centering around a heterosexual, married-with-children relationship," write Dr. Habbershon and Donath. They explain that while modern families represent about one-third of American households, "71% of investors believe financial guidance, and the solutions that accompany that guidance, are geared toward 'traditional family relationships.'"

And these modern families are seeking help. "A triad came into an investment center and asked, how do we do financial and retirement planning for the 3 of us?" recalls Mary Brennan, vice president of the Fidelity Center for Family Engagement. The recommended strategies may be different for them—and so many others.

The future for non-nuclear families

"We need to take a step back and reevaluate some basic terms," says Morgan. "What does it mean to be a family? What does it mean to be a parent? We have to broaden those definitions and make them more dynamic."

For example, if tax forms only allow categories of single, married, or head of household, where does that leave 2 mom friends who live together with their kids? What about 3 people who have an equal romantic partnership? How might a company's family leave policy be applied, for example? Or hospital visitation rights usually reserved for just one partner?

"The big challenge is that a lot of governments are stagnant," says Morgan. "They're not good at adapting quickly or embracing new concepts. By the time things get approved and voted on, it's been years of people already living like this."

He points to the changing framework around gender, the new vocabulary, and the changing language that has started to emerge on official forms. "But look how long it took to get done," he says.

There are some signs of progress. During the COVID-19 pandemic, 2 Massachusetts towns, Cambridge and Somerville, granted spousal rights to partnerships between 3 or more people. In Canada, there are cases of 3 parents all serving as the legal guardians of the same kids.

Looking ahead, it's unclear how nontraditional families will affect the economy. The rise in single parents could mean more families experiencing financial instability, says Sawhill. "The evidence is clear that when you only have 1 adult in the family, there's going to be a higher poverty rate," she says.

On the other hand, multigenerational families might keep poverty from rising because people pool together income, Reyes says.

Ultimately, Americans are being squeezed, leading them to look for alternative solutions. "I heard about a single person who bought a house with another couple," says Reyes. "I thought it seemed crazy, but these things are happening."

Whatever the future holds, adds Morgan, "it's going to mean more diversity and a need to create more options to accommodate the different family structures that are out there."

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