William Frawley was actually almost six years older than the actor portraying Ethel's father (Irving Bacon).
Ethel announces she'll star in a film in Hollywood. As luck would have it, she and Fred are later cast in supporting roles in a film (#4.18).
This episode opens with the foursome about to leave Amarillo, Texas, where Ethel phones her father to tell him they're on their way. The first shot is the exterior of their lodgings, The Texas Ann Motel, which was an actual establishment. Ironically, the real-life Texas Ann Motel was in Albuquerque (not Amarillo), located on Route 66, demolished in 1976.
In "The Million Dollar Idea" from Season 3, Ethel's middle name was Roberta. In this episode, her father calls her Ethel Mae.
Risë Stevens sang "My Hero" in the 1941 film version of "The Chocolate Soldier."