“It doesn’t,” he said.

She looked at him, suspending her relief.

“We could transplant a kidney into Mrs. Bergstrom from a cadaver but we wouldn’t get an immunological match as close as yours and your sister’s.”

“Is that because we’re twins?”

“If you were identical twins your tissues would be a perfect match. But from what Melanie has told us, you’re fraternal twins. If that’s so, the match won’t be perfect but your tissues would be accepted by your sister’s body more readily than any other we could find.” He shrugged. “It would give her that much more chance.”

“A girl has only two kidneys,” she said.

“Not every girl.”

She was silent. She opened her eyes and looked at him.

“You only need one kidney to live. Lots of people have been born with one kidney and have lived to ripe old age.”

“And some people have donated one kidney and then something has gone wrong with the other one. And they’ve died,” she said quietly. “I’ve done my homework.”

“That’s right,” he admitted.

She took a cigarette from her bag and absently lit it herself before he could move.

“We can’t minimize the risks. We can’t even, with any morality, urge you to do it. It’s completely a personal decision.”

“There are lots of things involved,” she said wearily. “I’m supposed to go to the West Coast to make a movie about the days of the big bands. It’s what I’ve been waiting for.”

This time he remained silent.

“You don’t understand how it is between some sisters,” she said. “I did a lot of thinking about it on the plane last night.” She smiled mirthlessly. “I’m the older sister, did you know that?”

He smiled and shook his head.

“Ten minutes. You’d think it was ten years, the way my mother always carried on. Melanie was the baby doll with the pretty name and Margaret was the dependable older sister. All our lives I’ve been the one who’s had to take care of her. From the time we were sixteen we were singing in joints where we were afraid to use the toilet and I had to make sure she wasn’t off behind the bandstand with some lousy trumpet player. Six years of that. And after one good season with Leonard Rathbone’s television show we began to make it and we got booked into Blinstrub’s and our agent introduced her to his Boston cousin. And that was the end of the sister act.”

She got up and walked to the window and stared out at the parking lot. “Look, I was happy for her. Her husband is a nice, square kid. College graduate, makes a decent living. He treats her like a queen. I didn’t give a damn about the act. I started out all over again as a single.”