Task: Question Generation
Input (English): The film recounts six months in the 2005-06 life of five children with autism and their parents in Los Angeles, California as their children write and rehearse for an original stage production.[2] Among the children, Henry Stills is an expert on dinosaurs and a budding comedian; Adam Mandela Walden plays the cello and sings in the film. The other children featured in the film have one or more things they excel at doing if only given the training they need to communicate and develop those skills.Several of the parents appearing in the film are well known in his or her own right. For example, Rosanne Katon-Walden was Playboy magazine's Playmate of the Month for its September 1978 issue and her husband Richard Walden (Operation USA) is the president and chief executive officer of Operation USA, an international organization that shared the 1997 Nobel Peace Prize for its work as part of the International Campaign to Ban Landmines. American guitarist and singer/songwriter Stephen Stills is "Stills" in the renowned rock band Crosby, Stills &amp; Nash (and Young). They and the other parents round out a cast of real-life parents struggling with their strained marriages while dealing with the sometimes overwhelming needs of their children with autism.
Output (English): Who is an American guitarist?