Given the following context:

The film is based on a real event that occurred in 1968 in Billings, Montana, the hometown of screenwriter T. J. Lynch.A popular locally produced children's television show, Happy Herb & Froggy Doo, features magician Happy Herb and his wisecracking marionette sidekick, Froggy Doo. Froggy Doo is stolen and held for ransom, and the Federal Bureau of Investigation is called in to investigate. Elliott Plumm used to watch the show, but now feels he is too grown up to do so any longer. His five-year-old brother, Rocky, is a Froggy Doo fan, however. Their father, Mick Plumm, is a recovering alcoholic and unemployed ex-boxer who believes Elliott's birth prevented him from going to the Olympic Games 12 years earlier. Mick's emotionally distant relationship with Elliott is causing Elliott to become emotionally troubled. Their mother, Roxie Plumm, is the only breadwinner in the family, and keeping her husband sober and attending to her job means she has little time for her children.

answer the following question:

Who is the stolen marionette a sidekick to? 

Happy Herb