Johnny Whitaker appeared just a few episodes earlier The Confrontation (1970) playing a different child, Willie.
When they are all reading the newspaper Lisa is reading the funnies but as they keep switching shots back and forth the paper also goes back and forth from being held folded then unfolded.
Frank Ferguson appeared in this show as Doc John Stuart. However, on Petticoat Junction, a Green Acres sister program, Frank Ferguson appeared as Dr. Barton Stuart.