Toots Thielemans passed away this weekend at the age of 94. Here is the full conversation John Carney had with him. Toots Thielemans was a Belgian jazz musician most famous for playing the harmonica. His most notable work is probably the harmonica in the Sesame Street theme song. Toots did the whistling for the Old Spice commercials. He also recorded music with the likes Ella Fitzgerald, Pat Metheny and more.