William "Bill" Henry Cosby Jr. is a member of the Junkyard Gang, and Russell's older brother. In the Junkyard Band, he plays the drums (made from a foot-petal trashcan and a metal box) As his name suggests, he is an animated version of the series' creator, Bill Cosby. (although the real Bill Cosby himself is a live-action narrator)
Like Fat Albert, Bill is usually the voice of reason in the gang, although at times a little more stubborn. As the older brother of Russell, he is often trying to keep his little brother Russell out of trouble, though not always successfully.
Bill is an African-American teenager based on Bill Cosby, when he was younger.
He wears a white long-sleeve shirt, blue pants, and white sneakers with blue circles on each side.
In the movie, Bill's shirt is now blue with a picture of the Brown Hornet, and his shoes are now black and white.