Continuity mistake: When Doug sits down to read his book, he has his book on his tray. This then disappears as the shot changes. (00:11:20)
Visible crew/equipment: When Doug and his friends are moving the TV back downstairs, in the first shot just as Spence announces his finger is getting crushed, a camera operator with camera are visible on the left side of the screen. (00:12:45)
Continuity mistake: Arthur and Doug are sitting with beers in the basement. Arthur doesn't open his beer, but the sound of a bottle opening can be heard and suddenly his beer has foam all the way up to the top of the bottle. Arthur stands up and the bottle is still unopened. It cuts to Doug, then back to Arthur with no beer at all. Again it cuts to Doug, then back to Arthur, and he is holding the unopened beer again. (00:18:30)
Fixer Upper - S1-E12
Continuity mistake: Doug finishes playing the tennis game on the TV with Arthur and goes into the kitchen to get the Cheese Doodles. While talking to Carrie, he puts the Cheese Doodle package on the table with a can of cola behind it. He then goes to get a glass from the cupboard and in the next shot you see the cola is in front of the Cheese Doodles. (00:17:30)
Visible crew/equipment: During the driving scene at 00:07:35 you can see a stage wall on the set to the right when the lights pass over the car. (00:07:35)
Continuity mistake: In the overhead shot when Carrie parks there is no-one around. From the internal shot, there are 2 people visible through the side windows. (00:00:40)
Revealing mistake: When we see the montage of Doug working as a manager, in one overhead shot you can see the image on the PC is simply stuck on to make it seem like it's on. (00:08:50)
Revealing mistake: Even after receiving the gift basket from the neighbors, the Heffernans are still awakened by their barking dog. When Carrie rushes downstairs Doug stops her at the front door, and the entire left window has been removed (for camera access) from its frame, so there's a large empty hole. (00:13:10)
Visible crew/equipment: While Doug and Carrie are in the kitchen talking about Doug's job, right after Carrie says, "Wait him out 5 or 10 years," in the next shot facing the sink, we can see the end of the kitchen set at the right side of the screen. (00:14:00)
Visible crew/equipment: At the start, while Doug and Carrie are in the jewelry store, in the shot of Doug swinging the shopping bags at the overhead surveillance camera, we can see a production camera at the left side of the screen. Then in the next shot, from the POV of the surveillance camera, the edge of the store's set is visible at the right side of the screen. (00:02:05)
Continuity mistake: When Doug goes to meet up with Ray, Richie zips up his jacket. In the next shot his jacket is unzipped. (00:06:20)
Continuity mistake: Carrie and Arthur are talking about Carrie making a Thanksgiving meal, and as they are talking the frozen meals in Carrie's trolley change position between shots. (00:03:10)
Continuity mistake: Ritchie asks if Doug is trying to get him drunk and has both hands out of his pockets. Camera cuts and one hand is now in his pocket. (00:05:00)
Continuity mistake: When watching the film, Doug's legs goes from the table to the floor between shots. (00:03:10)
Train Wreck - S1-E20
Continuity mistake: When Carrie turns up at IPS, she holds out the coloured char with two hands then one depending on the shot. (00:09:50)
Train Wreck - S1-E20
Continuity mistake: When Ritchie is pretending to be Carrie, Doug has hold of his cue with both hands. Camera cuts and he's not holding the tip any more. (00:06:05)
Continuity mistake: Just after picking the big turkey, Carrie's bag keeps changing place in the trolley. Note its position in relation to the handle. (00:06:00)
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.