Sorry, Younger Siblings: Study Shows First-Born Kids Are Smarter

first born study hero

Science might have just put an end to the epic sibling feud. A new study shows that first-born children are smarter than their younger siblings. To which we say, “We knew it, Little Sis.”

In a study published in the Journal of Human Resources, economists at the University of Edinburgh and the University of Sydney found that first-born children tend to score higher on IQ tests than their little brothers and sisters. The researchers used data collected by the US Bureau of Labor Statistics, which assessed nearly 5,000 children every two years from birth until age 14. Results showed that even as early as one year after being born, first children have higher-level thinking skills than their siblings.

The reason behind these smarty-pants first borns? Parents are more likely to engage in mentally stimulating activities, like playing music or reading, with them. Once baby number two comes around, parents (understandably) get a bit distracted and tend not to participate in as many thought-provoking behaviors.

But don’t get too upset, younger siblings. First-borns are also 20% more likely to develop short-sightedness. So, ha.

9 Easy Ways to Stimulate a Baby’s Mind and Body

Abby Hepworth


Abby Hepworth is an RRCA-certified running coach who has worked in fashion for over 10 years. Want to know what shoes are in this season? She's got you. Need recommendations on...
read full bio