They grow up in the same home, eat the same food, share the same genes (and sometimes the same jeans), but somehow siblings are often no more similar than complete strangers.
A new study from BYU found that parents’ beliefs about their children — and the comparisons they make — may cause differences to be magnified.
“Parents’ beliefs about their children, not just their actual parenting, may influence who their children become,” said BYU professor and lead author of the study Alex Jensen.
The study, published Friday in the Journal of Family Psychology, focused on siblings and academic achievement. Jensen and co-author Susan McHale from Penn State looked at 388 teenage first- and second-born siblings and their parents from 17 school districts in a northeastern state. The researchers asked the parents which sibling was better in school. The majority of parents thought that the firstborn was better, although on average, siblings’ achievement was pretty similar.