Cheap Saks - S6-E15
Continuity mistake: Near the end of this episode, after Trish Flintoff leaves, Doug is telling Carrie and Holly that she's a nice person. Doug is looking at Carrie, then the shot changes and he is immediately looking down and reaching towards his back pocket. It also looks like he's trying not to laugh. (00:19:35)
Cheap Saks - S6-E15
Continuity mistake: At the art gallery, the way Doug is holding the program instantly changes a couple times; arms crossed/uncrossed, program folded/unfolded. (00:02:20)
Cheap Saks - S6-E15
Visible crew/equipment: While Doug reaches for the phone when Trish is calling you can see where the kitchen wall is ending on the set. (00:11:53)
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.