Visible crew/equipment: After Arthur coerces Carrie into inviting quite a few others to their dinner she reminds him of his inside voice, then, when Arthur walks away to get the gherkins in aisle 4, there are multiple visible T-marks taped to the floor behind Carrie. (00:07:05)
Train Wreck - S1-E20
Visible crew/equipment: At IPS, while Doug gives his speech about using heavy package stickers, in the shots facing the drivers seated at the table, the end of the IPS set and a crew member are visible at the right side of the screen. (00:08:45)
Train Wreck - S1-E20
Visible crew/equipment: When Arthur asks Doug for help with the epitaph, the green and red tape markers are visible on the floor in front of the dishwasher, where Doug stands. (00:12:00)
Visible crew/equipment: Doug whisks Carrie to the boardwalk straight from the train after work, and when Doug points to the booth with plush frogs, a camera is visible on the left side of the screen as it moves out of shot. (00:17:20)
Visible crew/equipment: When Doug uses the ridiculous RV horn and startles Carrie awake, as she walks from the sofa to the front door, the overhead studio lights are visible at the top of the screen. (00:11:40)
Strike One - S3-E5
Visible crew/equipment: When it cuts from Doug singing with the barbershop quartet, to Doug and Carrie standing in the garage with the new vehicle, the end of the garage set wall is visible on the left side of the screen. (00:09:35)
Visible crew/equipment: During the flashback, when Carrie walks over to Doug at the side of the house, and he zips himself up, in shots facing Doug, a crew member and production equipment are visible on the right side of the screen. (00:20:10)
Visible crew/equipment: During the flashback, while Doug is waiting on the porch Carrie rushes out then gets into her car to take off, and in the next shot facing the front door, the reflections of the camera operator, wearing a white baseball cap, and the camera are visible on the window. (00:12:35)
Soft Touch - S2-E22
Visible crew/equipment: At the start, in the shots facing Carrie and Doug while they're in the car, we can see a screen atop the roof on the driver's side of the car with its reflection on the windshield (and its shadow on the car's hood). This is gone in the overhead long shots. (00:00:10)
Visible crew/equipment: When Arthur is talking about the store clerk hiding yam's out the back, there is an orange marker on the floor between the two men. (00:14:20)
Visible crew/equipment: When the store clerk walks off from talking to Arthur an orange T marker is visible where he was stood. (00:14:50)
Road Rayge - S1-E9
Visible crew/equipment: When Doug's paper gets ripped up, look at Ray and Doug's feet. A blue and white tape marker is visible by each of them. (00:06:10)
Visible crew/equipment: When Spence is leaving after dropping off the pictures a stage light is reflected in the door. (00:08:50)
Mean Streak - S4-E3
Visible crew/equipment: Doug is debating smashing the woman's parcel. As she opens her door a black tape marker is visible on the floor. (00:15:50)
Visible crew/equipment: In the church just as the minister tells Doug and Carrie to take a seat, two white tape markers are visible on the red carpet. (00:05:30)
Visible crew/equipment: When Doug says he doesn't want to look after Arthur in the bedroom, there are 4 tape markers visible on the floor at the foot of the bed. (00:14:30)
Wish Boned - S7-E17
Visible crew/equipment: When Doug starts to walk over to the flight attendant, a second camera slides into the shot for a few seconds to the right of the screen. (00:12:36)
Visible crew/equipment: When the camera cuts into the wide shot of Carrie leaving the store, the camera rig to the left of the screen is almost entirely visible. You can see it follow Carrie around for a good 10 seconds. (00:10:35)
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.