The Simpsons: 10 Moments More Important Than You Realised
8. Sideshow Bob's Family
Sideshow Bob is one of The Simpsons' greatest recurring characters. Originally beginning life as Krusty the Clown's long-suffering sidekick, Bob takes on a dark edge when he is revealed to have framed the harlequin for armed robbery.
Over the years, Bob has become one of the show's most reliable villains, as he goes to more and more extreme lengths to get revenge on the person who sent him to prison - Bartholomew J. Simpson.
The character got a nice bit of backstory in Season 8, when we get introduced to his brother, Cecil, voiced by David Hyde Pierce - and this casting is actually a very meta nod to another classic comedy show.
Pierce plays Niles Crane in Frasier, the brother of the title character. And who plays Frasier Crane? None other than Sideshow Bob's voice actor, Kelsey Grammer.
Not only is this a very clever, very subtle joke, but it also acts as foreshadowing for another member of Bob's family. In Season 19's Funeral for a Fiend, we meet Bob and Cecil's father, as voiced by the late John Mahoney.
Who's John Mahoney? Well, he's the actor who plays Frasier and Niles' father in Frasier. Brilliant.