Slate's Jacob Weisberg in The Bush Tragedy writes that first-born George's childhood was shadowed by being displaced in his parents' affections by younger brother, Jeb. George was a runty screw-up; Jeb was tall, smart, serious. Weisberg says George's realization that his parents expected Jeb to carry on the family's political legacy helped propel George to sober up, run for office, and reclaim the mantle of primogeniture. Weisberg writes that their mother, Barbara, regretted that George's rise stymied the presidential ambitions of her favored younger son—shades of Rebecca helping the younger, cleverer Jacob steal the birthright from the thicker Esau.
There is a special piquancy to adult sibling rivalries. The finale of this season's Top Chef had an extra edge by having the dueling Voltaggio brothers, Bryan and Michael, as the last contestants. When asked why he should be selected, Michael responded, only half-jokingly, "Because I don't want Bryan to be Top Chef." (He got his wish.) The estranged novelist sisters A.S. Byatt and Margaret Drabble have both scathingly portrayed the sister relationship in their writing, and critics have observed that besting each other in the literary rankings has helped drive their work.
But a frequent sibling strategy for avoiding head-to-head comparisons is to carve out a separate niche. Sometimes this is easy—one sibling is a math whiz, another a musician—so each shines in his or her realm. But sometimes the niche becomes a prison cell, with families reducing each individual to a shorthand: the smart one, the helpful one, the troublemaker. As Apter points out, not only can this be crushingly reductive; it also defines us by the qualities we supposedly lack. If your sister is the pretty one, then you aren't. As people leave the family and take on new identities in the world, it can be maddening to return home and find they are expected to take up their discarded labels. And when a sibling comes back with an improved identity built on new accomplishments, it can threaten the established hierarchy of the other siblings.
There's a theory in the sibling psychological literature called "deidentification," which finds that siblings aren't so much choosing their own identity as choosing what not to be in response to who their siblings are. In The Bin Ladens, Steve Coll describes the necessarily complicated dynamics that result when one father has 54 children. Most of the Bin Laden siblings grew up to embrace the entree to the West the father's money gave them. In this psychological portrait, you could say that Osama Bin Laden, who made it his mission to destroy the United States, where many of his siblings were educated, lived, and did business, demonstrated the ultimate, homicidal case of deidentification.
In a series of studies of sibling relationships, one of psychologist Kramer's surprising and encouraging findings is that siblings don't necessarily expect to be treated equally by their parents; what they want is fairness. Many of the siblings interviewed acknowledged that their parents didn't treat all the children the same all the time. But they accepted there might be a legitimate explanation. "The kids were searching for reasons for parents' differential treatment," she says. For example, some would say, "They have to spend more time with my brother than me, because he needs more support than I do."
Kramer found that the reasons the child came up with may not even match the parents' perceptions of their own behavior. She says actual and perceived differential treatment—or favoritism—is a largely taboo subject. But she suggests families would be helped by being able to talk about this. Having a shared family understanding of how people are treated and why reduces sibling acrimony.
The parental ideal of equal treatment of all their children can be experienced by the children as worse than different but equitable treatment, Kramer's research found. She tells the story of a colleague who was one of five siblings. Each December they all received identical sweaters for Christmas, no matter their gender, body type, or color preferences. These perfectly matched gifts, instead of eliminating resentment, made them all feel discounted as individuals.
After the childhood squabbles have faded away, good sibling relations can batten us against the difficulties and loneliness of our own old age. An article by Joshua Wolf Shenk in the Atlantic about the work of psychiatrist George Vaillant, who has conducted a long-term study of Harvard graduates, reported 93 percent of men who were thriving at age 65 had had a close relationship with a brother or sister. A survey by Duke University medical sociologist Deborah Gold categorized the types of sibling relationships of a group of 60 people over 65. The majority, 80 percent, felt strong ties toward their siblings, and would expect to ask, or be asked, for support in a difficult time.
Being aware that it's normal to have a lifetime of clashing impulses about our siblings can help us understand our early struggles and keep them from being replayed each holiday. This Christmas, we could recall the story of Cain and Abel and ignore whether it was a gift from our sibling that the parents seemed to like best.
Emily Yoffe received research support for this article from a Templeton-Cambridge journalism fellowship in science and religion.