John Costa, born in 1922, died in 1996. Some of the best jazz music ever created was made by piano virtuoso John "Johnny" Costa for Mister Rogers.

"Every day, Costa and his trio performed in the studio as the show was recorded. In addition to the show's recognizable main theme, they played the trolley whistles, Mr. McFeely's frenetic Speedy Delivery piano plonks, the vibraphone flute-toots as Fred fed his fish, and all of Rogers' entrance and exit songs—all live." —Wikipedia