Growing up with a sibling of the opposite sex may give both siblings greater confidence in their ability to form healthy, romantic relationships with others, compared with those who have same-sex siblings, suggests a study in the Journal of Youth and Adolescence.

The study found that opposite-sex siblings saw themselves as increasingly capable of attracting and interacting with the opposite sex during the period from early to late adolescence. But no significant changes in so-called perceived romantic competence were found...