Visible crew/equipment: When Doug says that Carrie is making progress with her room, a boom shadow can be seen moving along the door. (00:03:30)
Visible crew/equipment: When Doug walks out of Carrie's room, a boom shadow can be seen just outside the room on the wall. (00:03:35)
Visible crew/equipment: When Carrie and Doug head out to the garage the first time, a boom mic is reflected in the door's glass. (00:04:05)
Visible crew/equipment: Stage lights can be seen reflecting off the fake apples in the table center-piece at the hotel. (00:02:25)
Dire Strayts - S2-E8
Visible crew/equipment: When Doug says about watching the game at his on the big screen, a boom mic drops into shot very quickly. (00:01:45)
Dire Strayts - S2-E8
Visible crew/equipment: When Carrie asks what Deborah is like, on the cupboard door above Doug you can see the reflection of a boom mic moving around. (00:04:45)
Dire Strayts - S2-E8
Visible crew/equipment: When Carrie storms out into the back yard, Doug follows. When he does, the kitchen door stays open and if you look at the glass it reflects all the stage equipment above the set in the kitchen. (00:07:00)
Party Favor - S2-E13
Visible crew/equipment: When Doug goes back to the house after unsuccessfully scraping the frost off the car, a stage light is reflected in the window to the right of the front door. As Doug approaches the door his own shadow passes over this reflection. (00:01:30)
Party Favor - S2-E13
Visible crew/equipment: When Doug and Carrie are arguing about Danny coming over, you can see a stage light (not on) through the door window. We can also the neighbours garage, which we know from many outside shots of the Heffernan's backyard, is not that close to the house. (00:01:50)
Frozen Pop - S2-E15
Visible crew/equipment: At the very beginning, when Carrie walks in, a boom mic is visible above her. It then quickly moves out of shot. (00:00:05)
Frozen Pop - S2-E15
Visible crew/equipment: When Doug goes to scrape the car, a stage light is reflected in the iced up windows. (00:01:05)
Frozen Pop - S2-E15
Visible crew/equipment: When Doug is scraping the car, watch carefully and you can the the reflection of someone off screen behind the camera move. (00:01:10)
Frozen Pop - S2-E15
Visible crew/equipment: While Doug is scraping the windshield in the wide shots, the end of the street backdrop and production equipment are visible at the upper left side of the screen. (00:01:15)
Frozen Pop - S2-E15
Visible crew/equipment: When Arthur puts his big red jacket on and goes downstairs, Carrie follows and tape markers are visible on the floor by the door. (00:16:30)
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.