Whereas Julia had understood so little about her illness, her ten children knew its name, knew its damage, and had a dim sense that they were genetically susceptible to their mother's rare form of the disease. In 1991, their ages, which ranged from twenty-seven to forty-nine, nearly paralleled the years during which the disease's early onset usually struck. They had read that mutations connected to it had been found, but that didn't make their at-risk situation necessarily any more real. No certain signs of it had appeared among them, and they lived their lives around other thoughts -- their attachments, their marriages, their careers, and the sons and daughters they were bringing into the world. They'd been told that the disease mostly hit twins; perhaps it would travel no further than their mother and her identical twin Agnes, who had developed Alzheimer's some ten years after Julia. Perhaps the Tatro twins' affliction had been some sort of genetic fluke. Maybe it had been only that.