Yep: Research shows that first-born sons (I have no idea why daughters weren't also studied) are 24 percent more likely to become CEOs or top managers than second-born sons, and 28 percent more likely than third-born sons.
According to the researchers:
"We find that earlier born men are more emotionally stable, persistent, socially outgoing, willing to assume responsibility, and able to take initiative than later-borns.
"We also find that earlier born children are more likely to be in occupations that require leadership ability, social ability and the Big Five personality traits. When we investigate possible mechanisms, we find that the negative effects of birth order are driven by post-natal environmental factors. We also find evidence of lower parental human capital investments in later-born children."
In some ways that makes sense. Older kids tend to be placed in "leadership" positions: babysitting their younger siblings, playing the big brother role... they get early practice at taking responsibility. And they learn how to deal with pressure.
Yet the researchers also found that when first-borns reach their teenage years, they're more likely to spend time on homework and more likely to read books. Later-born sons average spending approximately one hour less each week on homework than their older brothers.
In case you're wondering, the cause seems to be nurture, not nature. Plenty of studies show that parents typically expect more from and are more strict with their first-born children (of either sex) than subsequent children. Plus the second, third, fourth, etc. kids typically receive less adult supervision.
Hence the statement by the researchers, "We also find evidence of lower parental human capital investments in later-born children," a nice way of saying that parents tend to back off with subsequent kids. (I know I did.)
Interestingly, later-born sons are more likely to be entrepreneurs. "Birth order affects occupational sorting; first-born children are more likely to be managers, while later-born children are more likely to be self-employed," the researchers say.
Boys with older brothers are also more likely to go into creative professions; it certainly makes sense that greater freedom can lead to innovation and originality.
What does all this mean to you?
One, find ways for all of your kids to start gaining leadership skills. No matter what they do professionally, leadership skills are important. Help all of your kids learn to take initiative. If you have high standards, maintain those standards for all of your kids.
And never forget that raising children may always be an imperfect science... but showing your kids how much you love them will always be the perfect way to parent.