The episode won an Emmy Award for Outstanding Sound Mixing for a Comedy Series or a Special.
Raymond Flynn was the Mayor of Boston from 1984-1993.
The barbershop quartet is played by the 139th Street Quartet. Founded in 1975, they won multiple medals in international competitions, ranking as high as second place. They also hold two platinum records as backup singers for two Neil Diamond Christmas albums.
Monty Ash who plays the 106-year-old Mr. Weaver, was actually only 80 years old at the time of the episode, and he died at the age of 89 in 1998.
The hospital Lilith and Frasier go to is Massachusetts General Hospital, also known as Mass General.