The bones were the same as always; in her cheeks the underlying structure was sharp and severe and elegant. But there wasn't enough flesh on them. They were reminiscent of what happens at puberty, when the body starts changing in ways that aren't well coordinated. That was it. Kristen had become a child--it was in her innocent eyes-- except that her body was now the flesh of a child over the bone structure of an adult. It scarcely seemed like the same person from the last time. She had crossed some mystical divide. She was holding a large rag doll--where did she get that? Ally wondered--and humming the tune of the ditty that ended with "_Now I know my ABC's. Tell me what you think of me_." "She can't talk," Stone was saying. "I mean, actually communicate. Or at least she doesn't seem to want to. I've already tried. But isn't what's happened incredible? There's never been anything like this in history. The replacement cells are making her body newer and newer, so she's getting younger and younger." Ally walked over, slowly, and tried to take her hand. She was grasping the doll and she violently pulled back. "Hey," she said, trying to muster a matter-of-fact air, "how's it going? Do you remember me?" "I don't think she recognizes you," Stone said in a stage whisper. "I wish I knew more about the biology of the brain, but I think there's some kind of aggressive replacement of memory synapses under way. I think it's one of those LIFO things. Last in/first out. She's regressing chronologically, but in reverse. Maybe she's lost use of language, the way Alzheimer's patients do. I don't know." Ally felt herself near to tears. "Van de Vliet was going to use antibodies from me to try to . . . something." "That was always a long shot," he said. "But now the preliminary tests he's just done on you indicate that the level of enzyme in you can be controlled very accurately. He's very excited." She turned back to him. "How do you know all this?" "I've become part of the story, Ally. That's not supposed to happen, but this is the only way to get it all firsthand. I have to live it. And guess what, I now know enough to write the book I've been waiting all my life to write. I have the punch line." "Which is?" "Stem cell technology goes to the very origin of life, and it may turn out that for once Mother Nature can be fooled. Dr. Vee's venturing into areas now where even he doesn't know what's going on. Ally, what's happening in this room is the biggest medical story since . . . Nothing begins to compare." Stone had lost it. There was true madness about him now. She walked back over to Kristen and leaned over and kissed her. Kristen stared at her in unfocused confusion, but then she smiled. "I'm alone in here. Will you take me outside? I want to find my mother."