The problem for scientists was that this whole idea of siblings as second class citizens never really seemed to hold up. After the researchers had learned all they could from the relationships in the family, mothers and other relationships, they still came up with some temperamental dark matter that was pulling at us, exerting a gravity on its own. And that could only be our siblings.
Humans are no different from animals. After we are born we do whatever we can to attract the attention of our parents, determining what our strongest selling points are and marketing them ferociously. Someone’s the funny one, someone’s the pretty one, someone’s the athlete, someone’s the smart one. Scientists call this “De-identification”. If my older brother is a high-school football player which if you saw my older brother you’d know he was not, I could become a high school football player, too and get at most 50% of the applause in my family for doing that.
Or, I could become student council president or specialize in the arts and get a 100% of the attention in that area. Sometimes parents contaminate the De-identification process, communicating to their kids subtly or not, that only certain kinds of accomplishments would be applauded in the home. Joe Kennedy was famous for this making it clear to his nine children that they were expected to compete with one another in athletics and were expected to win, lest they’d be made to eat in the kitchen with the help rather than in the dining room with the family.
It’s no wonder that scrawny second born Jack Kennedy fought so hard to compete with his fitter first born brother Joe often at his peril. At one point engaging in a bicycle race around the house that resulted in a collision costing John 28 stitches. Joe walked away essentially unharmed.
Parents exacerbate this problem further when they exhibit favoritism which they do overwhelmingly, no matter how much they admit it. A study I cite in this Time Magazine, covering in the book The Sibling Effect, found that 70% of fathers and 65% of mothers exhibit a preference for at least one child. And keep in mind here the keyword is exhibit. The remaining parents may simply be doing a better job of concealing things.
I’d like to say that 95% of all parents have a favorite, 5% are lying about it. The exception is my wife and me, honestly we do not have a favorite.
It’s not parents’ fault that they harbor feelings of favoritism. And here, too, our natural wiring is at work. Firstborns are the first products on the familial assembly line. Parents typically get two years of investing dollars, calories and so many other resources in them so that by the time the second born comes along the first born is already, it’s what corporations call, sunk costs, you don’t want to disinvest in this one, and launch the R&D on a new product.
So what we begin to do is say “I’m going to lean to the Mac OS 10 and let the Mac OS 11, come out in a couple of years.” So we tend to lean in that direction, but there are other forces at work, too. One of the same studies I looked at here, both here and in the book, found that improbably the most common favorite for a father is the last born daughter, the most common favorite for a mother is the first born son. Now this isn’t Oedipal, never mind what the Freudians would have told us a hundred years ago, and it’s not just that fathers are habitually wrapped around the fingers of their little girls, though I can tell you that, as the father of two girls that part definitely plays a role.
Rather, there is a certain reproductive narcissism at work. Your opposite born sons — your opposite gender kids can never resemble you exactly. But if somehow they can resemble you temperamentally you love them all the more. As the result, the father who is a businessman will just melt at the idea of his MBA daughter with the toughest nails worldview. The mother who is a sensitive type will go gooey over her son the poet.
Birth order, another topic I covered for Time and another topic I cover in the book plays out in other ways as well. Long before scientists began looking at this, parents noticed that there are certain temperamental templates associated with all birth rankings. The serious, striving first born, the caught-in-a-thicket middle born, the wild child of a last born. And once again when scientists did crack this field they found out mom and dad are right.
First-borns across history have tended to be bigger and healthier than later borns, in part because of the headstart they got on food in an area on which it could be scarce. First-borns are also vaccinated more reliably and tend to have more follow-up visits to doctors when they get sick. And this pattern continues today. This IQ question is, sadly — I can say this as a second born — a very real thing, first-borns have a three point IQ advantage over second-borns and second-borns have a 1.5 IQ advantage over later borns, partly because of the exclusive attention first-borns get from mom and dad, and partly because they get a chance to mentor their younger kids.
All of this explains why first-borns are likelier to be CEOs, they are likelier to be senators, they are likelier to be astronauts and they are likelier to be earn more than other kids are. Last borns come into the world with a whole different set of challenges. The smallest and weakest cubs in the den, they’re at the greatest risk of getting eaten alive, so they have to develop what are called low power skills. The ability to charm and disarm to intuit what’s going on in someone else’s head, the better to duck the punch before it lands. They are also flat out funnier which is another thing that comes in handy because a person who’s making you laugh is a very hard person to slug.
It’s perhaps no coincidence that over the course of history some of our greatest satirists: Swift, Twain, Voltaire, Colbert, are either the last borns or among the last in very large families.
Most middle borns don’t get quite a sweet a deal. I think of us as the flyover states. We are — we’re the ones who fight harder for recognition in the home. We’re the ones who are always raising our hands while someone else at the table is getting called on. We’re the ones who tend to take a little longer to find their direction in life. And there can be self-esteem issues associated with that. Now, withstanding the fact that I’ve been asked to do TED so I feel much better about these things right now.
But the upside for middle borns is that they also tend to develop denser and richer relationships outside the home but that advantage comes also from something of a bit disadvantaged simply because their needs weren’t met as well in the home.