I don't know much about Billy Preston; over here in the UK he's known mainly for being one of the contenders for the 5th Beatle. I didn't know that he was a child star, until I came across this video of him performing with Nat King Cole when he was just 11 years old.
He was also a great dancer, as this appearance with Ray Charles shows.
And this version of Summertime is really something special.
I think I'll have to investigate some of Billy's recordings. Let me know if you know of any good ones.