主题：【文摘】Time上的一篇文章 -- 闲看蚂蚁上树

But as much as all the fighting can set parents' hair on end, there's a lot of learning going on too, specifically about how conflicts, once begun, can be settled. Shaw and his colleagues conducted a years-long study in which they visited the homes of 90 2-year-old children who had at least one sibling, observing the target kids' innate temperaments and their parents' discipline styles. The researchers returned when the children were 5 and observed them again, this time in a structured play session with one close-in-age sib. The pairs were shown three toys but given only one to play with. They were told they could move onto the next one only when both agreed it was time to switch and further agreed which toy they wanted next.

That, as any parent knows, is a scenario trip-wired for fights--and that's what happened. The experimenters ranked the conflicts on a five-point scale, with one being a single cross word and five being a full-blown brawl. The next year, they went to the same children's schools to observe them at play and interview their teachers. Almost universally, the kids who practiced the best conflict-resolution skills at home carried those abilities into the classroom.

Certainly, there are other things that could account for what makes some kids battlers in school and others not. But the most powerful variables--parents and personality--were identified and their influence isolated during the course of the two-year-long observations. Socioeconomic status, an X factor that bedevils studies like this one, was controlled by selecting all the families from the same economic stratum. Distill those influences away and what is left is the interaction of the sibs. "Siblings have a socializing effect on one another," Shaw says. "When you tease out all the other variables, it's the play styles that make the difference. Unlike a relationship with friends, you're stuck with your sibs. You learn to negotiate things day to day."

It's that permanence, researchers believe, that makes siblings so valuable a rehearsal tool for later life. Adulthood, after all, is practically defined by peer relationships--the workplace, a marriage, the church building committee. As siblings, we may sulk and fume but by nighttime we still return to the same twin beds in the same shared room. Peace is made when one sib offers a toy or shares a thought or throws a pillow in a mock provocation that releases the lingering tension in a burst of roughhousing. Somewhere in there is the early training for the e-mail joke that breaks an office silence or the husband who signals that a fight is over by asking his wife what she thinks they should do about that fast-approaching vacation anyway. "Sibling relationships are where you learn all this," says developmental psychologist Susan McHale of Penn State University. "They are relationships between equals."

• How not being Mom's favorite can have its advantages

MULTICHILD HOUSEHOLDS CAN BE NOTHING short of palace courts, with alliances, feuds, grudges and loyalties, all changing day to day. Perhaps the touchiest problem in most such families is favoritism.

Parents feel a lot of guilt over the often evident if rarely admitted preference they harbor for one child over another--the sensitive mom who goes gooey over her son the poet, the hard-knocks dad who adores his tough-as-nails daughter. If favorites exist, however, it may be not the parents' fault, but evolution's.

The family began as--and remains--a survival unit, with parents agreeing to care for the kids, the kids agreeing to carry on the genes and all of them doing what they can to make sure no one gets eaten by wolves. But the resources that make this possible are limited. "Economic means, types of jobs, even love and affection are in finite supply," says psychologist Mark Feinberg of Penn State. Parents, despite themselves, are programmed to notice the child who seems most worthy of the investment. While millenniums of socialization have helped us resist and even reverse this impulse, and we often pour much of a family's wealth and energy into the care of the disabled or difficult child, our primal programming still draws us to the pretty, gifted ones.

Conger devised a study to test how widespread favoritism is. She assembled a group of 384 adolescent sibling pairs and their parents, visiting them three times over three years and questioning them all about their relationships, their sense of well-being and more. To see how they interacted as a group, she videotaped them as they worked through sample conflicts. Overall, she concluded that 65% of mothers and 70% of fathers exhibited a preference for one child--in most cases, the older one. What's more, the kids know what's going on. "They all say, 'Well, it makes sense that they would treat us differently, because he's older or we're a boy and a girl,'" Conger reports.

At first, kids appear to adapt well to the disparity and often learn to game the system, flipping blatant favoritism back to their shared advantage. "They'll say to one another, 'Why don't you ask Mom if we can go to the mall because she never says no to you,'" says Conger. But at a deeper level, second-tier children may pay a price. "They tend to be sadder and have more self-esteem questions," Conger says. "They feel like they're not as worthy, and they're trying to figure out why."