The video shows 9-year-old Dane Miller belting out Whitney Houston's 1993 hit "I Have Nothing," in the backseat of his father's car.
"We did just watch a documentary on [Houston] about a month ago, and so he started downloading her songs and that was the one he got stuck on," said Dane's mother, Danna Miller.
The video was recorded Monday and a family shared it on Facebook, according to KPTV. In less than a week, it's already had more than five million views, making it almost as popular as the Whitney Houston version.
Danna says she was blown away by the Internet's response to the video.
"Just reading the comments, they're so sweet. I'm getting emotional," said Danna. "Some other families who have Down Syndrome children have posted pictures with their kids."
The family has created a YouTube channel titled "Amazing Dane," to share more videos of Dane performing his favorite songs.