Learn to Draw with Jon Gnagy
Long before Bob Ross' Joy of Painting, there was Jon Gnagy's television show Learn to Draw. It was produced sometime in the 1950's. Gnagy's reassuring tone helps sooth the beginning artist's nagging feeling that they can't draw. Whether Bob Ross saw Gnagy's films or not, Gnagy's soothing tone would become the presentation arch-type of the Joy of Painting.
The video above is an infomercial for the Famous Artists School - a legit correspondence course for learning how to paint and draw, and create commercial illustrations and cartoon drawings. Sadly FAS closed their doors in 2016. If you can find copies of the course, they are well worth adding to your art book library.