STEVE INSKEEP, host:
It's MORNING EDITION from NPR News. I'm Steve Inskeep.
RENEE MONTAGNE, host:
And I'm Renee Montagne. Good morning.
Whether you have siblings or not, you're probably familiar with the stereotypes about birth order - the bossy, high-achieving firstborn, the spoiled baby of the family. That kind of thing. And I'm a middle child. What about you, Steve?
INSKEEP: Oh, I'm a middle child too. Second of three. There we go.
MONTAGNE: Oh, there we go. And never bossy. I don't know. So what about the birth order stereotypes? We're looking at sibling relationships this Thanksgiving week. And today NPR's Allison Aubrey reports that assumptions about birth order go way back.
ALLISON AUBREY: If you've never heard of an English law established in the year 1540 called the Statute of Wills, trust me, it wouldn't have done much for you, unless, that is, you were a firstborn son. Back then, oldest sons had huge incentives to stay on track and please their parents. Because by tradition they were set to inherit almost everything their family owned.
Now, you may think any firstborn effect would be long gone. But if you look around, there are still vestiges of it. And even though most parents don't intend to treat children differently, experts say many firstborns can grow up in a different world.
Monica Hanson, who's the mom of two children, says with her oldest daughter she wanted her to try it all.
Ms. MONICA HANSON: Oh, gosh. She did everything. I put her in tennis lessons. I put her in dance lessons, art classes, music classes, swimming classes. Oh my goodness. There's so many. Now I have a son who's seven years younger than her and he doesn't get as many classes as - exposed to as many things as she did. So maybe it is true.
AUBREY: It seems to happen generation after generation. Hanson says realizing that she's parenting her two kids differently makes her think about her own childhood. As the oldest of four siblings, she did get the ballet lessons and a lot of attention early on. But she also felt as the firstborn that her parents had high expectations for her, in terms of achievements, helping out with her younger siblings, and in following the rules. For instance, she remembers strict curfews compared to what her parents enforced with her sisters.
Ms. HANSON: I don't even think they did it on purpose. But they just realized I was the oldest so I was kind of expected to do a lot of things. You're expected to be unselfish. You're expected to just get it done. You can't complain. And you just accept it. At least I did.
AUBREY: To this day, Hanson is still seen by family and friends as the doer -the boss, the person who can hold everybody together. In her life, doing charity work and raising kids, she's never outgrown what she considers to be her firstborn instincts.
Ms. HANSON: Let's say, for example, if I decided that I'm going to run a banquet for my daughter's school or something like that, even if I haven't done it before, I will just do the best that I can so everyone knows about the event and that all the details are taken care of.
AUBREY: You're going to put in 100 percent.
Ms. HANSON: Absolutely.
AUBREY: Experts say that the access firstborns typically have to parents and to resources tends to nudge the oldest child towards achievement. And nothing makes the firstborn effect more clear than the makeup of the U.S. Congress.
Psychologist Richard Zweigenhaft of Guilford College first examined the status of firstborns back in 1972 by looking at Washington power brokers.
Professor RICHARD ZWEIGENHAFT (Guilford College): I expected that there would be a disproportionately high number of firstborns among members of Congress. And that's exactly what I found.
AUBREY: Out of 121 congressmen and senators, Zweigenhaft found that 51 were firstborns, compared to 39 middle children and 31 were lastborns or babies. It wasn't a huge overrepresentation of oldests, but the difference is too significant to ignore.
And over the years, many surveys and studies have found that firstborns edge out later-borns in lots of high-achieving professions, from corporate CEOs to college professors to U.S. presidents and Supreme Court justices. There's even evidence that firstborns are about three IQ points smarter than their second-born siblings.
But Zweigenhaft says despite these advantages, birth order is far from deterministic.
Prof. ZWEIGENHAFT: I'm not sure I would say that birth order plays a strong role in who we become. What I keep saying is birth order contributes to who we become.
AUBREY: After all, it's never entirely predictable how birth order may end up influencing our adult lives. We're all more or less amalgams of many childhood influences, from teachers and peers to random life events, including turns of good luck and bad.
Monica Hanson says one of the traits she sees in herself and all of her sisters can't possibly be the work of birth order. She chalks it up to the spirit and values they learned from their dad.
Ms. HANSON: He said, you know, you can do anything you want in this world, but whatever you do, just make sure it's what you want. And don't compare yourself to anyone.
AUBREY: Hanson says he preached the same message to all of his children, from the firstborn to the baby.
Allison Aubrey, NPR News.
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