TV Shows where a secondary character quickly or slowly overtook the show?
There were a few post about Jaleel White (aka, Steve Urkel) not to long ago. This got me wondering what others television shows were overtaken by a secondary character.
I can think of at least two others:
Fonzie on Happy Days (which almost became completely about him) and Eddie Haskel on Leave it to Beaver (where did he come from?)
Any others?