The on-again-off-again relationship between Sam and Diane in the first few seasons ... She was one of the only cast members ...

The main Cheers cast actually reprised their roles from the classic sitcom in animated form on The Simpsons once, with one noteworthy exception.

When actor Nicholas Colasanto passed away slightly before the beginning of Cheers Season 4 ... that the rest of the cast had a hard time with Harrelson at first. "We wanted to kick his ass ...