The "Mapplethorpe" book of nudes which Homer inadvertently picks up is a reference to the work of Robert Mapplethorpe, a photographer whose work caused controversy due to its focus on the underground bondage and sadomasochistic BDSM scene of late 1960s and early 1970s New York City.
The word "Pneumonoultramicroscopicsilicovolcanoconiosis" which Grandpa uses in asking why Marge doesn't look well, is reputed to be the longest word in the English language; it is synonymous with the shorter word "pneumoconiosis" and refers to the lung disease also known as miner's lung.
Dan Castellaneta provides the voices for both Homer and Grampa. Castellaneta therefore had to talk to himself when he recorded the voices of the two characters in their interactions for this episode. Castellaneta says that it is hard for him to do Grampa's voice for an extended period of time because it is "wheezy and airy".
Homer is shown shaving off his stubble, which grows back moments later. This gag was also done in Some Enchanted Evening (1990), where Homer has a clean shaven look for precisely seven seconds, then his stubble regrows.
Originally, the subplot relating to the kids was supposed to end with their learning from Ralph Wiggum what was actually going on. However, it was cut from the episode when it aired because the writers couldn't figure out how to justify someone like Ralph as having any knowledge about sex.