Continuity mistake: Marie and Frasier are sitting on the couch when Marty comes home, and her arms noticeably change position as the shot changes. Then, a few shots later, she has her hands on her legs above her knees, but in one quick shot her hands are wrapped around her knees - without enough time for her to have changed naturally.
Continuity mistake: In the opening scene, Roz and Frasier are in Cafe Nervosa, and she is snoozing, while a half-eaten muffin sits in front her. As she wakes up and talks to Frasier, the muffin appears whole again. She leaves and Martin comes in and takes her seat. A shot then shows the muffin as half-eaten again, even though no one has touched it.
Answer: Nanny G (Nanette Guzman - played by Laurie Metcaf) has been a children's entertainer for twenty years, and tells Frasier, "Do you know what it's like to play the same character for 20 years?!" The joke is that Kelsey Grammer has been playing Frasier Crane since 1984, when the character first appeared on "Cheers", so Kelsey in real life has been doing just that!
Super Grover ★