Many problems cosmic rifts have happened between Cheers and Frasier, to name a few:
- Nancy Marchand played the mother of Frasier on Cheers, by the time "Frasier" came out the character was supposed to be dead.
- Frasier was once quoted as saying he was an only child, and both his parents were dead, and he was an orphaned at the age of 30. This conflicts with the fact he had his mom on the show earlier in the series, and then his father has resurfaced on "Frasier".
- Peri Gilpin, and John Mahoney both appeared in "Cheers" and "Frasier" as different characters.
- Frasier appeared to be married twice on "Frasier" but one never hears about his first marriage on "Cheers", perhaps he lied to deceive Lilith Sternin, as he lied about his relationship with Diane Chambers during courtship.
In addition the only two regular cast members on "Cheers" who have yet to appear on "Frasier" is Ernie 'Coach' Pantusso because of death, and Rebecca Howe.
Frasier has appeared on three shows, "Wings", "Cheers" and "Frasier" all portrayed by Kelsey Grammer.