Camden opened the door himself. She could see his effort not to look worried. “You didn’t have to drive out, Susan; I’d have come into the city!”

“No, I didn’t want you to do that, Roger. Mrs. Camden is here?”

“In the living room.” Camden led her into a large room with a stone fireplace, English country-house furniture, and prints of dogs or boats, all hung eighteen inches too high; Elizabeth Camden must have done the decorating. She did not rise from her wing chair as Susan entered.

“Let me be concise and fast,” Susan said, “I don’t want to make this any more drawn-out for you than I have to. We have all the amniocentesis, ultrasound, and Langston test results. The fetus is fine, developing normally for two weeks, no problems with the implant on the uterine wall. But a complication has developed.”

“What?” Camden said. He took out a cigarette, looked at his wife, and put it back unlit.

Susan said quietly, “Mrs. Camden, by sheer chance both your ovaries released eggs last month. We removed one for the gene surgery. By more sheer chance the second was fertilized and implanted. You’re carrying two fetuses.”

Elizabeth Camden grew still. “Twins?”

“No,” Susan said. Then she realized what she had said. “I mean, yes. They’re twins, but non-identical. Only one has been genetically altered. The other will be no more similar to her than any two siblings. It’s a so-called normal baby. And I know you didn’t want a so-called normal baby.”

Camden said, “No. I didn’t.”

Elizabeth Camden said, “I did.”

Camden shot her a fierce look that Susan couldn’t read. He took out the cigarette again, and lit it. His face was in profile to Susan, and he was thinking intently; she doubted he knew the cigarette was there, or that he was lighting it. “Is the baby being affected by the other one’s being there?”