Hungry Man - S1-E21
Continuity mistake: At the start Arthur goes from cutting bananas to having his hands on the side in between instant cuts. (00:01:10)

Hungry Man - S1-E21
Continuity mistake: At the very end when Carrie walks out the level of foam on Doug's beer bottle changes between shots. (00:21:20)
Answer: Sara hasn't been mentioned in later episodes, and it suggested in later episodes that she never existed, and that Carrie is an only child. Kevin James stated that the producers couldn't think of an good plots to use with Sara, so they left her out.