Some 80 percent of older moms admit they have a favorite among their grown children, according to a new Cornell University/Louisiana State University pilot study, and about 80 percent of children said they always knew it. But when asked which kid was mom's favorite, most adult children get it wrong.

"Most adult children greatly overestimate how likely their mothers were to name them as the 'closest child,' but regardless of whom they identify as mom's favorite, they're usually wrong," said Karl Pillemer, who reported on his study at the Gerontology Society of America annual meeting Nov. 15 in Cincinnati. Pillemer is an associate professor of human development at Cornell and co-director of the Cornell Applied Gerontology Research Institute.

In one of the first studies to look at parental favoritism in later life, Pillemer and his long-time collaborator Jill Suitor of Louisiana State University -- currently a visiting professor at the University of Toronto -- conducted intensive, face-to-face interviews with 30 elderly mothers, ages 65 to 75 years, from diverse backgrounds. They also interviewed 46 (71 percent) of the mothers' grown children.

"Most of us think about family problems or violence as the biggest secrets in families," said Suitor, who pointed out that although mothers were very reluctant to identify a favorite, most still had one. "It's amazing to me how much more hesitant people seem to be with talking about favoritism among their children."

The researchers found striking discrepancies between what the mothers and their adult children reported on the emotional closeness between them.

"In particular, mothers tend to report greater closeness and fewer problems among their children than do the adult children. And the more conflict in a family, the greater the discrepancy between mother and child reports," Pillemer said.

The reports of closeness between a mother and grown children, however, was in much greater agreement when the "favored" child responded.

Pillemer and Suitor also found that how a mother feels about her grown children seems to be depend on a great deal more than a grown child's actions and feelings.

"They are largely influenced by the child's social structural position -- gender, marital status, parental status and educational attainment -- when compared with other siblings, as well as the child's personal history, such as whether he or she had problems growing up and whether the mothers believed those problems were in the child's control or not," Pillemer explained.

Interestingly, the favorite was often a child who had physical or psychological problems growing up that were not in his or her control. In addition, a daughter was more likely to be identified as the favorite child, particularly if her social place in life was similar to her mother's when compared with other children in the family.

In interviewing the grown children, the researchers found:

• Children were correct in identifying their mothers' favorite only 41 percent of the time.
• Adult children were much more candid in reporting their problems than their mothers were. They were twice as likely as their mothers to reveal they had ever had a drinking or alcohol problem or a problem with the police; three times more likely to report they had ever had serious school problems; and five times more likely to admit they had ever had problems with peers.

"Research, including our own, suggests that parents' well-being is negatively affected by their children's problems, especially voluntaristic problems that might reflect poorly on parents, and that probably increased intergenerational conflict," Pillemer said. "If parents underreport their children's voluntaristic problems, such as substance abuse and arrests, which our study suggests they do, then the influence of children's problems on parents' well-being probably has been underestimated."

He notes that although the study sample was small, the findings were provocative because they were so strong. Next, he and Suitor plan to interview 600 families, including fathers, to study the effect of parental favoritism on parents and grown children.

"We know that the quality of an older person's relationships with his/her children is very important to psychological well-being, and it now looks like it may be normal for parents, to some extent, to differentiate among their children and identify a favorite," Pillemer concluded. "Yet grown children should find it reassuring that their relationship with their older parents are dependent on many other factors besides the child's individual actions and feelings."

The research was supported, in part, by grants from Cornell and the National Institute on Aging.