Continuity mistake: When Doug is handing the deodorant back to Arthur the way he holds it changes between shots. (00:06:15)
Continuity mistake: When Tim asks Doug if he wants to tee off back at the start of the hole rather than halfway down the fairway, he is pointing with his golf club. Camera cuts and he isn't. (00:15:35)
Soft Touch - S2-E22
Continuity mistake: When Doug is getting into bed while talking to Carrie about selling water filters, his grip on the duvet changes instantly. (00:10:00)
Continuity mistake: When they are in the kitchen Carrie's purse switches from shoulder to shoulder when she tells Doug the good news.
Continuity mistake: When the nurse walks away from Doug, she walks away, camera cuts and she starts to walk away again. (00:07:25)
Deconstructing Carrie - S7-E15
Continuity mistake: Doug is sitting on the couch making club music sounds and moving his hands when Carrie reaches out and touches his face to make him stop; then his left hand is instantly on the arm rest. (00:13:10)
Party Favor - S2-E13
Continuity mistake: When Doug is reading his speech to Arthur, Arthur's legs are crossed or uncrossed depending on the angle. (00:09:30)
Strike Out - S3-E7
Continuity mistake: When Arthur sits down for his meal, there is a bottle on the table. The lid is either on or off depending on the shot. (00:03:30)
Continuity mistake: When Carrie asks Arthur how a legless dummy will protect her on the subway, her arms are either on the table or off, depending on the shot. (00:10:30)
Soft Touch - S2-E22
Continuity mistake: When Doug is telling Arthur about the filters, there is a leaflet on the table. Between camera cuts, this leaflet is constantly changing position. (00:13:25)
Queasy Rider - S2-E1
Continuity mistake: When Carrie says to Doug that he can't have a bike, her hand are behind her back. Camera cuts and now her bag is on her shoulder and her hands are on her bag. (00:03:00)
Queasy Rider - S2-E1
Continuity mistake: When Arthur gets the iron, he has it down by his side. Camera cuts and now it's up in front of his chest. (00:06:30)
Queasy Rider - S2-E1
Continuity mistake: When Doug and Carrie are arguing about the smoking for the first time, the cigarette has burnt down nearly half the length in a few seconds. Cigarettes don't burn that fast. (00:12:30)
Continuity mistake: The Heffernans' house is one of a row of identical brick houses. However from inside the Heffernans' living room, you can see out the side windows that the neighbour's house is beige with horizontal paneling.
Continuity mistake: At the start, when Carrie is talking to Arthur about being inseparable she has her jacket over her arm. Camera cuts and now she is putting it on instantly. (00:00:10)
Continuity mistake: When Carrie takes a drink from her cup of tea she is holding her cup with 1 hand in one shot and 2 in a second shot. (00:14:30)
Queasy Rider - S2-E1
Continuity mistake: As Doug is telling Carrie he hates the bike, his beer and crisps vanish instantly from the sofa. (00:19:20)
Strike Out - S3-E7
Continuity mistake: After Doug says "Let's hit the streets", Doug, Arthur, Deacon and Kirby go on a mini crime-spree. During this montage each characters outfit completely changes several times. They are also dressed very lightly for late October/early November in New York. (00:13:00 - 00:14:00)
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.