TUESDAY, Nov. 29 (HealthDay News) -- When a friend lets them down, girls may take it harder than boys do, a new study suggests.

It included 267 fourth- and fifth-grade students in North Carolina and Rhode Island who were shown 16 hypothetical stories in which a friend had violated a core expectation of friendship, such as belittling their worry over a sick pet or failing to do their part on a joint school project.

Girls were just as likely as boys to say that they would seek revenge against the friend, verbally attack the friend and threaten to end the friendship, the Duke University researchers found.

Girls were also more bothered by the transgressions, felt more anger and sadness, and were more likely to think the offense meant their friend did not care about them or was trying to control them.

"Our finding that girls would be just as vengeful and aggressive toward their friends as the boys is particularly interesting because past research has consistently shown boys to react more negatively following minor conflicts with friends, such as an argument about which game to play next," study co-author Steven Asher, a professor in the psychology and neuroscience department, said in a Duke news release.

"It appears that friendship transgressions and conflicts of interest may push different buttons for boys and girls," he added.

The study was co-authored by Julie Paquette MacEvoy, a former graduate student at Duke who is now assistant professor at Boston College's Lynch School of Education, which helped conduct the study. It was published online Nov. 22 in the journal Child Development.

More information

The NYU Child Study Center has more about children and friends.