King of the Hill Season 13 Episode 9 - What Happens at the National Episode Title:What Happens at the National.Episode Description:Propane Gas Convention in Memphis Stays at the National Propane Gas Convention in Memphis When Buck Strickland is invited to the National Propane Gas Convention as the newest inductee into the Propane Hall of Flame, he asks Hank to accompany him. Although Hank is honored, he quickly realizes his primary responsibility will be babysitting Buck and preventing him from getting into trouble. Hank's job is made that much more difficult when Buck meets his illegitimate son Ray Roy (guest voice Diedrich Bader) at the convention and stays out late carousing with him.