The first show featuring original music.
The background music for this show was used 3½ years later in HGWT's "The Savages" (S6 E27) wherein the autistic daughter sings it incessantly. It's a French childrens' song, "Auprès de ma Blonde" (Next to my Sweetheart). Extensively re-arranged here, it takes the average viewer some time to recognize it.