continued "To the outside world, we really have this protective attitude toward one another," says Nancy. "I can say something bad about Janna, but no one else better even agree with me."
Adolescence gave them opportunities: "We switched on our boyfriends, and they couldn't tell -- until we kissed. And then they went, 'Yuk -- which one are you?!' " It also started pulling them apart. "Outside the relationship I found I was very shy, and not controlling and domineering," says Janna. "And Nancy out there made friends who looked up to her, and she made the decisions and she ran with the ball."
This was probably a good thing. Many twins, the writers say, have difficulty breaking out of the comfort of their twin relationship and forming their own individual "outside" friendships.
On the other hand, Nancy and Janna say that often their gregariousness and trust developed within their own relationship made them vulnerable in outside relationships. "Often, we've ended up sharing too much of ourselves too easily, too soon," they write in the book. "Trouble holding back in new relationships is a by-product of the twin 'trust-bank.' Twins have a tendency to seek in others the closeness they have with their twins, because their twinship is the gold standard for love."
And therein, say Nancy and Janna, lies the real, underlying problem.
"As we grew up, our twinship did not. When we were together, no matter what our age, we would revert back to our childhood twin selves: Janna as dominant caregiver; Nancy as passive follower. We were unable to separate psychologically because our first separation [in first grade] had been so traumatic. We were trapped by an underlying fear of losing each other."
And Janna feared losing her caregiver role. "I remember when we first lived apart from each other [as college students]," says Nancy, "Janna's last words to me were, 'You'll never be able to balance your checkbook!' And 'You can't make it without me!' "
But living independently, Nancy earned a Ph.D. in biology, and Janna a doctor of jurisprudence degree. The two led successful, separate lives, although according to Nancy, "the phone bills were enormous."
Then in 1991, at age 33, despite the fact that Nancy had shifted to San Diego, gotten a job, and married, Janna couldn't stay separated any longer. "I'd told Nancy that I felt we had to live together again to help me let go of my dependence on our twinship," writes Janna in the book. "My feeling of being incomplete without her would not be healed until I could understand us as individuals."
It was a disaster.
"Within minutes of entering Nancy's house, I surveyed it and drew conclusions on the rearrangements that would be required to make it 'home.' I had pushed a well-worn button for Nancy. Childhood memories of my control over her came rushing back. For the first time ever [Nancy] attacked me with a viciousness of a lioness protecting her cubs. 'This is my house! You are a guest! I like it the way it's decorated, and you will not be allowed to change anything!'"
It was the moment that forced both sisters to "aggressively examine" their relationship. For the next seven years they worked on "detaching from our twinship." They even interviewed 17 other sets of twins. The book documents the results.
And yet today, here in Nancy's house, the two appear closer than ever. In their account of their adventure on Mount Kilimanjaro, the fact that Nancy's husband Stu was there didn't even rate a mention. Apparently, Nancy's fear was of losing her sister, not her husband.
"Poor Stu!" she says. They both laugh. "He perpetually goes through life feeling he's in second place. Janna and I, now that we've quit our jobs and are writing together, we spend all day together. And Stu will come home and she'll call me, and we'll be on the phone talking. And he'll say, 'What else could you possibly have to talk to her about?' It's not like we're ever going to run out of things to talk about. We just are each other's favorite plaything. Stu realizes that he can never be as close to me as Janna, and that's not a comfortable place for a significant other. You're used to being the number-one person in your mate's life. Stu and I do go on vacations together, and I try very hard to have weekends just for us. But it doesn't change the fact that Janna's still the most important. I'm closest to her."
On the way out, we're looking up at an Indonesian three-face mask. The center one is being squeezed in by the others. It looks as if it's screaming in agony. "Stu!" say the twins. "Stuck in the middle! We're in an eternal triangle. He says all the time, 'I married twins.' "
One in 80 live births in the U.S. are twins. A third of those are identical. The rates are increasing. The twins say they hope the book will help this growing number of floundering parents.
"The best thing my mom has said in years was when she finished reading the book. She put it down and looked at us and said, 'I wished I'd had this in 1957.' That was the year we were born," says Janna. "No one knew anything about multiples then."
I ask if they've considered having children of their own. They're unanimous. "If we could be guaranteed we'd have twins, we probably would have both had children," says Nancy. "...because I can't imagine," says Janna, finishing Nancy's sentence, "how one person goes through life by themselves, without this constant soul mate."
Since this interview, Nancy says she has left her marriage and now lives with Janna.