Visible crew/equipment: When Doug tells Carrie "eyes off" someone can be seen moving on the stairs behind them due to a foot appearing in shot and shadows moving. However no-one else is at home other than Doug and Carrie. (00:10:40)
Visible crew/equipment: When Deacon shows up with no shoes he steps inside the house and there is a white tape marker visible where he stops. (00:15:20)
Continuity mistake: When Carrie is reading from the leaflet, the way she holds it changes depending on the shot. (00:17:35)
Inner Tube - S3-E17
Continuity mistake: At the start at IPS, Doug's tie is looped over itself twice. Camera cuts and now it's not looped at all. (00:02:30)
Visible crew/equipment: When we first see Doug on a bike in an overhead shot the camera rig is reflected in a car windscreen. (00:17:50)
Factual error: In this episode Doug is denied getting a better route when it's given to the new guy because he's "better looking." As member of a union, Doug most certainly would have been given precedent over any new driver.
Visible crew/equipment: When Carrie gives Doug the card, the top of the set is visible behind them. (00:10:40)
Continuity mistake: When Carrie turns round and tells Doug that she's telling Kelly about the card, the bottle top on the table is constantly changing position without being touched. (00:11:40)
Visible crew/equipment: When Doug says about Kelly being in the wrong he puts his arm up in the air which shows the top of the set and some equipment. (00:14:00)
Continuity mistake: When Carrie is unpacking the shopping at the start she holds up an empty bag that magically folds itself flat between camera cuts. (00:01:50)
Visible crew/equipment: When Doug arrives at the airport and we see the two gentlemen writing names on a board, everyone has tape markers at their feet. (00:03:20)
Continuity mistake: When Doug is writing on a board, he holds the board at the end or the top depending on the shot. (00:03:30)
Visible crew/equipment: When Carrie comes back saying she can't swap the flights, there are various tape markers visible on the floor. (00:19:00)
Continuity mistake: The Saskeys are Doug's neighbors in this episode despite them having moved away back in the season 2 episode "Soft Touch" (00:02:30)
Revealing mistake: When Carrie leans on the fence to hide from the Saskeys, the fence moves. Fair enough Carrie is not a professional carpenter and has put the fence up in an afternoon. However, Tim, explains that the fence is not likely to fall due to how well Carrie has built it. (00:06:00)
Visible crew/equipment: When Doug gets the beach ball, all the stage lights are reflected in it. (00:14:00)
Continuity mistake: When Tim and Doug are talking about the pool overlooking the property, the way Tim holds the ball changes between camera cuts. (00:15:00)
Continuity mistake: When Carrie realises Doug has been in the pool, the magazine in Doug's hand vanishes instantly. (00:18:20)
Continuity mistake: When the beach ball sails over the fence, Doug picks it up and holds it to his face, making his right side of his shirt wet. Throughout that scene, his shirt is dry, and then wet again.
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.