Factual error: While Rob is roaming the house with a gun in his hand he chops the metal tube that the wood burning stove in the living-room is connected to. However since in real life the metal tube would be thick and insulated the tube he dented with his hand at that speed wouldn't have been damaged at all. Also, it could have broken his hand or at least sprained his hand where he wouldn't be able to use it or feel like using it.
Factual error: Rob says to his doctor that they have catfish at his home yet you never see the catfish ever. The only time you see fish in this series is on a plate or in the episode "The Night the Roof Fell In" which weren't catfish. (00:11:33)
A Surprise Surprise Is a Surprise - S2-E30
Factual error: Buddy asked Sally "why haven't you had a birthday...?" Yet a few episodes ago (Season 1 Episode "Where you been, Fassbinder?") Sally had a birthday she cried and cried. Buddy and Pickles, Rob and Laura were all there.
A Man's Teeth Are Not His Own - S2-E13
Factual error: Rob is in the middle of eating a sandwich. You can't break a tooth on a sandwich unless it's frozen, cement, glass or made of ice.
Suggested correction: Rob specifically said he broke the tooth on a chicken bone that was in the sandwich.