"It is extremely painful to watch this," her mother says. "To see your child just disintegrate before your eyes."
But after Alison died, research initiated by other Canavan families paid off.
They donated money and their children's blood and tissue to start a research project on the disease. A screening test was developed, and work began on a cure.
Yet, as CBS News Correspondent Sharyl Attkisson reports, without the families even knowing it, their children's genetic material was patented by one of the research partners, Miami Children's Hospital.
The hospital then imposed strict controls on the screening tests, and demanded royalties for each test performed.
"For somebody to say in the name of the almighty dollar that they are going to limit the number of people that can have access to this test, to me is just outrageous," says Mike Ossip.
Miami Children's Hospital argues it spent more on research than it's likely to ever get back, and that research will be stifled if there's no way to recoup costs. But it's not the first time the emerging market for genes and body parts has raised the ethical question - are the patients' best interests taking a backseat to their profit-potential?
The landmark case in this new frontier was that of John Moore and his amazing spleen. Back in the 1980s, doctors treating Moore for cancer at the University of California discovered he had spleen cells that could have special curative powers. So special, the university patented them and made millions selling the rights to a biotech company, all without Moore's knowledge or consent.
Eventually, Moore found out his cells had been sold and took his case to attorney Chris Angelo.
"The crux of the John Moore case is that a patient owns his own body, his own tissues, his own DNA," says Angelo.
The California Supreme Court disagreed, saying what happened to Moore might be unethical, but it wasn't illegal. People, the court ruled, have no property rights to their own bodies.
Moore spent the next decade fighting for patients' rights, before he died last year. What bothers his daughter Kara Saxby today is how his doctors secretly viewed him as a commodity.
"They seemed to be so concerned with his health and yet they were still just taking his blood and doing things with it that he didn't know about," says Saxby.
The families who provided their children's genetic material for Canavan research are suing Miami Children's Hospital for breach of informed consent. The Ossips are watching closely.
"Obviously people are entitled to make money, but there's got to be a limit," Karen Ossip says. "This is not right."
But it's today's bio-reality. With the increasing value of our parts and virtually no protection from the government or courts, there's no way to know whether you're viewed as patient or commodity.