Wow! This little kid is Frank "Sugerchile" Robinson. amazing little kid, and looks like the playing is legit. This is the first I have seen him, so now I am going to do some more research, and see what I can come up with.
From what I have found he was a piano player as a kid. However, there seems to be some controversy over his age. Some people have written that he was 17 or so when that film clip was made. Also there seems to be some confusion on whether he is still alive or not. One website says he died of a drug overdose, while some people posting on Youtube insist that he is playing at a local blues fest. I haven't found any information about the blues fest to figure out if it is him or not. I will update again when I get some more information.