My Rivals, My Solace . . . My Sisters

"We're like sisters," women say of their friends, meaning they're very close and completely for each other, like the friends in "The Sisterhood of the Traveling Pants." But then there's the moment in Edward Albee's play "A Delicate Balance" when a husband says that his wife and her sister "are at each other like a couple of . . ." and his daughter finishes his sentence: "Sisters?"

For each other, at each other: Sisters can be either or both. The same could be said of people in any close relationship. Yet there is something special about sisters -- specially gratifying and specially fraught.

I am a linguist who studies how conversation shapes relationships. I am also the youngest of three sisters -- a defining aspect of my identity. So I decided to study the relationships among sisters, not only because I have two, but because sisters typically talk a lot. They tend to talk to each other more than they talk to their brothers and more than brothers talk to each other, and they tend to get more personal in their conversations. I interviewed more than 100 women about their sisters -- and I couldn't help steering many casual conversations to this topic as well.

Once, at a party, a woman enthusiastically extolled her relationship with her sister. "When we meet we can't get enough of each other," she said. "She's my lifeline. I'm her lifeline." I wanted to learn more about this wonderful relationship, so I arranged to include this woman in my study.

To my surprise, when we later met for the interview, she began by telling me that she'd recently gone a year without speaking to her sister.

She and her sister had inherited a two-apartment building from their parents; each owned one unit. She had wanted to sell hers but had tabled the idea because her sister wasn't ready to sell, and she knew that the value of her sister's apartment would fall if she sold hers separately. Soon after, she left for an extended trip abroad. When she returned, she discovered that her sister had changed her mind -- and sold her apartment. Now her own apartment had plummeted in value. Her anger and hurt were so great, she could not bear to speak to her sister. But after a year she decided to let it go. She had only one sister and did not want to lose her.

The ideal I had heard about at the party was real, but it wasn't the whole story. A sister owns part of what you own -- a house, perhaps, or a less tangible legacy such as memories of your childhood. The way she manages that shared inheritance can raise or lower its value for you, or call its value into question.

A sister is the one person you can call in the middle of the night when you can't sleep, or the one who doesn't want to hear about your problems unless you're ready to do something about them. She's the one who is there when you need her, or the one whose absence when you need her hurts the most. She's the one you can brag to, or the one you'll never tell about your triumphs because she'd be jealous.

Among the many women I interviewed, I heard about a vast range of sister relationships, from best friends to worst enemies, but most were a combination of closeness and competition -- and the balance evolves over time. The one constant was comparison.

Renee and Jill are sisters who grew up in Washington. Renee, the older, had attended Spelman College in Atlanta, whereas Jill had attended Howard University and had lived at home. Though her sister and an older brother had gone to college out of town, when Jill's turn came, their mother lamented, "I'm not going to have anybody here!" She promised Jill a new car if she stayed home. Howard University was fine, Jill said, but she envied her sister and brother because "they got to go away." Renee pointed out that their mother had been the one who suggested that Renee apply to Spelman.

It's not that their mother capriciously encouraged one and discouraged the other from following the same path. The order of their birth made going to college a different act for each of them. There is no equal protection clause in the family constitution.

We all feel wistfulness or regret about roads not taken. But if a sister took the road we rejected, or a road we never had the chance to travel, we are continually reminded of the destination to which it led. Differences in where you end up or in the opportunities you had may seem unfair, because you were born into the same family. But that's an illusion; it's a different family when each child is born. A sister is like yourself in a different movie, a movie that stars you in a different life.