The video, posted two weeks ago, shows Clara Bergs dancing step-by-step to the Coppelia comic ballet in her family's living room, circling around a small footrest and positioning her body using a nearby cabinet.
A small window inside the video shows a professional ballerina performing the dance, as Clara moves back and forth simultaneously with the grown-up dancer, whose moves she learned to copy.
Since it went up Clara's four-minute recording has gone viral with more than 430,000 views and attracted media attention around the world.
Half of the traffic has flooded in since Tuesday when the video was posted on the NBC "Today" show website.
Lisa Anderson, Clara's mother, said it's amazing how popular her dancing daughter has become.
"She's quite social now and she really likes to have an audience. This is like a big audience to her," she said.
"She loves performing."
Anderson said the attention has helped boost online donations for Clara's therapy to the point where her $4,000-treatment bill for this month is covered.
Clara also has DiGeorge Syndrome, a genetic disorder, and uses a special type of autism therapy called Intensive Multi-Treatment Intervention that isn't funded by the Ontario government.
Anderson said Clara started the unique program while on the waiting list for another form of treatment paid for by the province — she has since been approved — but is sticking with the IMTI therapy, which is going well.
Anderson said the massive popularity of the video hasn't completely sunk in yet for Clara, who is only beginning to learn how to use YouTube.
But the mother is floored by the outpouring of positive comments for the video, which has drawn roughly 1,300 responses from around the globe.
"I'm feeling overwhelmed because we've received so many fabulous comments (about) how inspiring Clara has been for so many people, and how her dance has moved them in so many ways."
"We've seen her dancing every day and didn't realize the impact she would have on the world," she said.
Anderson said that Clara developed an interest in ballet when she joined a community dance class three years ago, and has a "fabulous sense of rhythm."
She says Clara started practising the Coppelia ballet after her aunt showed her a video — and that another dance video is in the works.
Clara spent her first 16 months after birth at Toronto's Hospital for Sick Children, where Anderson said some doctors wanted to give up on Clara and not keep her alive.
The family refused.
"I'm glad we did what we did and said, 'No, we want to intervene and want to give that child an ability to reach her potential — whatever that potential is,'" Anderson said.
— Here's a link to the video: http://www.youtube.com/watch?v=0dUcI8mA5hs
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