(USA TODAY) — Marriage mostly makes people happier, and a close family “inoculates” many kids against despair, according to long-term research.

U.S. adults born in the 1920s were happier during the Depression if their parents had a strong marriage. Compared with equally deprived peers growing up in unhappy homes, “they were happier not only in childhood but adulthood, too,” says University of North Carolina sociologist Glen Elder.

A newer study of Iowa farm families with adolescents during the 1990s confirms that a good home can buffer youngsters against economic hardship. “These people were doing more poorly the longer they stayed in farming,” says Elder, the study leader. But multi-generational closeness prevailed. “Grandparents would drive long distances just to see the kids in plays or at sporting events.”

The teens who grew up in hard times remain, overall, very happy as young adults, Elder says. “It’s clear these strong relationships are a source of resilience for kids if there’s not much money.”

Marriage per se, even if it’s not such a great marriage, tends to improve well-being, says University of Chicago sociologist Linda Waite. In large surveys, 40% of the married say they’re very happy, compared with 22% of the never married and 18% of previously married.

Among those who live with a romantic partner, 24% are very happy; engaged couples are the only live-in partners as happy as married people, Waite says.

There’s some evidence that those who marry are happier to begin with, “but there’s much stronger research showing that once adults marry, their well-being improves,” she adds.

She’s analyzed large federal surveys that followed thousands of married people over five years. About 90% who say they’re happily married have spouses who also are pleased with the marriage. The happily wed who ended up divorced five years later became much less happy. That’s perhaps not surprising, Waite says.

But the stunner is that about two-thirds who were unhappily married at the outset said they were happy five years later. Meanwhile, the unhappily married who had divorced five years later were no happier than those who stayed with their original spouse.

The bottom line: “There’s a certain plasticity in marriage, an up-and-down. A lot of problems resolve over time, and married people tend to get happier,” Waite says.

“It’s a message some people disbelieve,” she concedes, “but they have unrealistic ideas about marriage.”

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