Yulinda Burkett will tell anyone who'll listen what feats her daughter has tackled lately.

Brianna can sit up on her own for more than 30 seconds. A couple of months ago, she walked five steps with a little help from mom. She eats a few ounces of food a day from a spoon.For most 4-year-olds, these are milestones passed years ago. Burkett knows this; she revels in the accomplishments anyway.

Brianna, who will turn 4 this month, has Canavan disease. The illness destroys the brain's white matter and affects its electrical connections. It claims nearly all victims before they're teens.

Six months ago, the little blond girl became one of the first children in the world to undergo an experimental brain treatment in an attempt to stop the progression of the disease.

Leaders in the only research program trying to find a cure for Canavan disease think the treatment, if successful, could lead to treatments for other diseases of the brain, possibly even Parkinson's disease.

To Burkett, any sign of progress in her daughter is a reason to hope that the treatment is slowing the illness's rampage.

"Being experimental, you never know what's going to happen. I go on day by day. This is today. I do what I have to do and enjoy it while it's here," she said.

Doctors said it is too early to tell from brain scans how effective the treatment was, but they said Brianna hasn't gotten any worse. They noticed the small changes in the little girl, too.

"She has shown some developmental progress normally seen in small children. But she's still well behind her age," said Dr. Ted Kurczynski, Brianna's neurologist at Medical College of Ohio Hospital.

Brianna is legally blind. She can't hold her head up. The disease has made her prone to pneumonia and seizures, and the medicine she takes to control them make her sleepy. The little girl can't walk or talk, and she is fed most of her meals through a tube in her stomach.

One of the most encouraging signs since the March treatment at Yale-New Haven Hospital in New Haven, Conn., is evident in Brianna's arms and legs. Once so stiff they stuck straight out from her body, they're a little looser.

When Burkett sets Brianna on her lap, talking and cooing to her the whole time, the girl unclenches her fists, something her mother said she rarely did before.

On a recent morning, Brianna napped in a tiny red recliner as country music videos played quietly on the television.

Brianna and her mom will go to New Haven and Philadelphia for tests Sept. 23 to check for progress. The little girl likely will have another injection in the spring.

There is reason to hope that the treatment could slow or stop the deterioration of matter in Brianna's brain, Kurczynski said. But nothing can repair the damage that's been done.

"The neurons can't reproduce in humans," he said.

The life expectancy of a child with Canavan disease is three to 10 years, but some reach their teens.

The single mother will take whatever improvement in Brianna she can get, whether it means her daughter will walk someday or just gain another year of life.

"When I see improvements, it's really exciting, because I want her to get better. But I try not to get my hopes up," she said.