 One episode called for Dr. and Mrs. Craig to visit Philadelphia.  Inspired by returning to Independence Square,  William Daniels (I) (qv) sang a few lines of the song, "Sit Down,  John!", from _1776 (1972)_ (qv). (The line was "Its hot as hell in  Philadelphia!") The moment was included in the episode. (He also  mentioned that there was something about being in the city of  Philadelhphia that just made him want to sing and dance). Daniels  played John Adams in that movie. In this episode Dr. Craig (Daniels)  also mentions to his wife that back in medical school he was  "obnoxious and disliked" which is also something said by John Adams  to his wife in "1776".