Children are more likely to be kind and caring if their siblings are, a Canadian study showed.
The study was published Tuesday in the journal Child Development.
Researchers said that younger siblings could contribute to their older sisters' and brothers' empathy in early childhood.
The findings provided new evidence about how family values were being built as older siblings were previously thought to influence their younger siblings' capacity to feel care and sympathy for those in need.
"Although it's assumed that older siblings and parents are the primary socializing influences on younger siblings' development (but not vice versa), we found that both younger and older siblings positively contributed to each other's empathy over time," said Marc Jambon from the University of Calgary, who led the study.
"These findings stayed the same, even after taking into consideration each child's earlier levels of empathy and factors that siblings in a family share, such as parenting practices or the family's socioeconomic status, that could explain similarities between them," Jambon said.
Researchers studied an ethnically diverse group of 452 Canadian sibling pairs and their mothers from a range of socioeconomic backgrounds.
They determined whether levels of empathy in 18- and 48- siblings at the start of the study predicted changes in the other siblings' empathy 18 months later.
The researchers videotaped interactions in the families' homes and mothers completed questionnaires.
Children's empathy was measured by observing each sibling's behavioral and facial responses to an adult researcher who pretended to be distressed and hurt.
However, the study found one exception, after they examined whether siblings' development of empathy differed as a result of age and gender differences between siblings.
"Younger brothers didn't contribute to significant changes in older sisters' empathy," Jambon said.
The influence of older brothers and sisters was also stronger in families in which the age difference between the siblings was greater, suggesting they were more effective teachers and role models, the study found.
The researchers have suggested to determine whether teaching one sibling, either older or younger, can in turn affect the empathy of the other sibling.
