Birth Order and Personality

The Birth Order Effect

"The one thing you can bet your paycheck on is the firstborn and second-born in any given family are going to be different," says Dr. Kevin Leman, a psychologist who has studied birth order since 1967 and author of The Birth Order Book: Why You Are the Way You Are (Revell). But how is it that a gregarious comedian and a reclusive, introspective thinker can be so different yet share the same genes? Psychologists like Leman believe the secret to sibling personality differences lies in birth order -- whether you're a first-, middle-, last-born, or only child -- and how parents treat their child because of it.

Meri Wallace, a child and family therapist for over 20 years and author of Birth Order Blues (Owl Books), agrees. "Some of it has to do with the way the parent relates to the child in his spot, and some of it actually happens because of the spot itself. Each spot has unique challenges," she explains.

Birth Order + Parenting = Behavior

Simply by virtue of being a couple's first child, a firstborn will naturally be a sort of experiment for the new parents, a mixture of instinct and trial-and-error. Perhaps this will cause the parents to become by-the-book caregivers who are extremely attentive, stringent with rules, and overly neurotic about the minutiae. This in turn may cause the child to become a perfectionist, always striving to please his parents.

In contrast, if the couple decides to have a second child, they might raise their second-born with less of an iron first due to their experiences raising their firstborn. They might also be less attentive to the second-born since there's another child competing for attention, and they probably will be less inclined to impulsively dial 911 every time the child breaks a sweat. This may cause the second-born to be less of a perfectionist but more of a people-pleaser due to the lack of attention he gets in comparison to his older sibling.

In short, it's not necessarily the fact that a child came out of his mother's womb first that he grew up to be a leader who talks a blue streak. Rather, it's the fact that his parents treated him as their firstborn child that shaped his attitude and behavior.