How would you feel if, after giving birth to your second child,
the doctor handed him to you and said, “Congratulations, but
watch out with this one because he’s more likely than your
firstborn to be a troublemaker”?
Well, that’s pretty much the conclusion that researchers from a
study led by MIT economist Joseph Doyle came to after poring over data from
thousands of sets of brothers from Denmark and Florida.
It's true Denmark and Florida are quite different when it comes to raising kids, and yet Doyle and
fellow researchers found that despite the differences in environments, there was something they had in common. In families that had two or more kids, second-born boys were 20 to 40 percent more likely to receive disciplinary action in school, and enter the criminal justice system, when compared to first-born boys and other siblings.
Oh, brother! But why? What makes second-born boys more likely to
act out? Well, there could be a lot of reasons, but one explanation for how
birth order may account for the difference is the influence of the first-born
on the second-born.
"The first-born has role models, who are
adults. And the second, later-born children have role models who are slightly
irrational 2-year-olds, you know, their older siblings," explains Doyle.
It’s important to keep in mind that second-born
boys aren’t predestined to a life of disciplinary run-ins or delinquency, so
don’t go buying your second-born striped pajamas or orange jumpsuit onesies just yet.
You might be asking: What about the girls? The study predominantly focused on boys, but when researchers looked at the data for sisters, they didn’t
find a significant difference between second-born girls and their siblings.