Accepting that birthday money from Grandma might improve her overall happiness.

A new study found adult grandchildren and their grandparents have a considerable effect on each other's psychological health.  Giving "tangible support" improved well-being in only grandparents, an American Sociological Association press release reported.

"We found that an emotionally close grandparent-adult grandchild relationship was associated with fewer symptoms of depression for both generations," Sara M. Moorman, an assistant professor in the Department of Sociology and the Institute on Aging at Boston College, said. "The greater emotional support grandparents and adult grandchildren received from one another, the better their psychological health."

For grandparents, "tangible support" (also called functional solidarity) could include anything from helping their grandchildren with the laundry to giving them money for a toll.

"Grandparents who experienced the sharpest increases in depressive symptoms over time received tangible support, but did not give it," Moorman, a co-author of the study, said. "There's a saying, 'It's better to give than to receive.' Our results support that folk wisdom - if a grandparent gets help, but can't give it, he or she feels badly. Grandparents expect to be able to help their grandchildren, even when their grandchildren are grown, and it's frustrating and depressing for them to instead be dependent on their grandchildren."

The research team looked at data from 376 grandparents and 340 grandchildren. The average grandparent was born in 1917 and the average grandchild in the study was born in 1964. The study participants were around 77 and 31-years old as of 1994, when the study was at its midpoint.

Researchers found grandparents who were able to help out their grandchildren either physically or emotionally were less likely to have symptoms of depressions, LiveScience reported. Grandparents that received help but did not give back were more likely to suffer from psychological issues.

The study also concluded it was important for grandparents to feel independent, but to have a "two-way supportive relationship" with their grandchildren.

"All people benefit from feeling needed, worthwhile, and independent. In other words, let granddad write you a check on your birthday, even if he's on Social Security and you've held a real job for years now," Sara Moorman, professor of sociology at Boston College, said, according to LiveScience.