 Although Frasier had mentioned on "Cheers" (in two episodes) that his father, a research scientist, had died, Angell, Casey, and Lee did not realize this was the case, as they were not working on "Cheers" during the season those two episodes were filmed.The creative team was already well into the development process when Grammer pointed out the discontinuity; they decided to overlook it, initially retconning the character's backstory.In a second-season episode, the discrepancy was resolved, as Frasier revealed he had lied to the "Cheers" gang about his father.