Birth order has long been linked to differences in cognition, with firstborn children often outperforming their later-born ...

A sibling-matched study design analyzing a cohort of more than 2 million singleton births was found to be inconclusive in ...

A surprising new study — or unsurprising, depending on who you are — suggests that the middle child takes the cake when it comes to certain personality traits. There's no denying that birth order ...

NEW YORK (Reuters Health) - A new study suggests that kids who are born only a year or two after an older sibling might be more likely to be diagnosed with autism than those with a bigger age gap. Of ...

Feel like your parents always favored your older sibling? They might have benefited from that more than you realize. A new study suggests all that extra attention makes first-born children smarter ...

A research study on siblings and alcoholic use disorder, The Development Unfolding of Sibling Influences on Alcohol Use Over Time, is worth noting. The researchers, who included professors and a ...

WASHINGTON — People who grow up with lots of siblings are more likely to marry — and to stay married — than are only children or those who grew up with one or two siblings, a new study has found.

A study published in PLOS Mental Health has explored whether having a sibling born preterm (before 37 weeks of gestation) affects the behavior of children born at term. In the study by the University ...