Everyone knows that mothers have a powerful influence on their children. Sometime in the 1970s science discovered that fathers are important, too. The 1990s are shaping up as the time we figured out that kids' development is deeply influenced by their brothers and sisters, and that siblings may be the source of most individual differences in development.
The reason why kids from the same family can grow up to be so different, says Judy Dunn, Ph.D., is that they are far more socially sensitive than we've given them credit for. From "a remarkably early age," at least the end of their first year, she reports in Current Directions (Vol. 1, No. 1), they monitor the affection, attention, and discipline their parents lavish on their sibs, and the warmth and pride they show in them. Then they make comparisons to themselves.
It's these experiences of differential treatment that shape kids, and turn family life into a daily drama for them. Those who get less maternal attention than their sibs become more worried, anxious, or depressed than other kids. And in families with greater differential parental treatment, there's more hostility and conflict between the kids.
It's in a child's best interest to understand family members and the social rules of the shared family world, says Dunn. In her portrait of the home as a hotbed of emotional comparisons, "from 18 months on children understand how to hurt, comfort, and exacerbate their siblings' pain," among other things. What makes her portrait so true-to-life is that it comes from direct observations of kids with their families.
Kids naturally differ in their ability to understand the causes and consequences of emotions and to sense what others are thinking. But those with the shrewdest social sense are the ones who see mom paying attention and responding to their sibs.
They even anticipate when a sibling will get attention --and make attempts to draw attention to themselves. "It takes a lot of skill to do," says Dunn. In daily drama of life, each kid is looking for a starring role.