Sibling Bonds: How Parents Dole Out the Cash Matters

portrait of two girls who don't like each other.
Sibling ties can be broken when mom and dad play favorites financially, giving one sibling more money than the other, research finds. (Image credit: Odua Images | Shutterstock)

When parents play favorites by giving one young adult child more money than the other, the whole family may lose out. That's because such favoritism can make for bad sibling relationships later on, new research finds.

Even so, the study, detailed in the August issue of the Journal of Marriage and Family, suggested when parents give one of their children other types of preferential treatment, such as greater affection and emotional support, sibling relationships weren't affected.

"Sibling relationships can provide very important support in adulthood. Parents may be unwittingly straining those relationships," said Dr. Victor Fornari, chief of child and adolescent psychiatry at Zucker Hillside Hospital in Glen Oaks, N.Y., who was not involved in the present study. [10 Scientific Tips For Raising Happy Kids]

No fair!

In the new study, Sonja Siennick, a psychologist at Florida State University, examined the relationships of nearly 1,500 sibling pairs included in a national database of adolescent health data. Study participants were members of a randomly selected group of middle- and high-school students who answered questions about relationships with their siblings in a 1996 interview.

At a second interview in 2001-2002, the students, then ranging in age from 18 to 27, answered questions about the type of emotional and financial support provided by their parents, as well as their current relationships with siblings. Nearly 600 of the sibling pairs were twins.

In families of siblings who recorded the highest levels of disparity in parental affection, the favored sibling reported receiving twice as much financial support as those who felt unfavored — an average of $229 versus $114 per year. Favored siblings were also 45 percent more likely to be living with parents than their sisters or brothers at the second interview.

Sibling differences in current parent-child affection and the living-at-home situation didn't seem to affect sibling relationship quality in young adulthood; however, Siennick found the amount of received parental financial support did. Siblings who received equal amounts of financial support were slightly more likely to report a good relationship with their brother or sister than siblings in which there was a $100 annual disparity in support. These findings suggest that money may be an especially valuable family commodity during the transition to adulthood, Siennick wrote.

Another recent study found that financial help from mom and dad to their young adult children was linked to a solid parent-child bond that got stronger as the amount of money given to kids increased.

Are parents playing favorites?

Though Siennick accounted for certain factors that could sway parents' differential treatment of children, such as gaps in age between siblings, gender and socioeconomic status, siblings could have underestimated or overestimated the parental favoritism. Parents were not interviewed, so it is impossible to know their rationale behind providing differential treatment between siblings.

"Kids often don't know what goes on behind the scenes that determines the way parents make decisions," Fornari said. For instance, maybe one sibling has a greater need for tutoring or a family's financial situation changes after one sibling has already grown up, he said.

Fornari noted that while sometimes parents really do play favorites, other times it may just be a child’s perception that one sibling is getting preferential treatment. Even so, these feelings are real, Fornari said, and they should be addressed with good communication.

"One of the most helpful things parents can do is to let the child know you appreciate how the child feels and that while you may share equal affection for each child, each sibling is different and may have different needs," he said.

Fornari added, "This study is a good reminder that parents need to be mindful of the way in which they demonstrate affection and support, because children are exquisitely sensitive to inequality, even into adulthood."

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