Continuity mistake: Just before Stewie says Grace, the glass between Brian and Stewie changes from water to milk between shots. Also, Brian's plate changes in the same cut. (00:21:05)
Continuity mistake: Quagmire's hair changes from being parted in the middle to slicked back to parted in the middle again while still cuffed to the bed. (As told in the commentary.) (00:45:50 - 00:47:40)
Continuity mistake: Just after Chris asks Vanessa not to argue in front of Pablo, Stewie (young) changes position in relation to Vanessa. (01:01:20)
Continuity mistake: When Lois goes into the bathroom and Peter is in the bath, she closes the door. We see it and hear it. Yet when the kids come in they walk through the already wide open door.
Continuity mistake: When Stewie and Brian are having martinis at the Drunken Clam, Stewie's olive gets out of his glass and onto the table in a shot-change. (00:28:20)
Continuity mistake: In the shower scene, pay attention to the candle on the far left. Its size changes between shots.
Continuity mistake: Just before Chris tells Stewie that swimmers shave all their hair off, the glass next to Stewie changes. (00:12:45)
Continuity mistake: When Stewie is proposing that 'Old Stewie' buys him a time travel watch, the garbage in the bin changes. (01:11:25)
Continuity mistake: When Brian barges in on Stewie in the bathroom, the shaving cream on Stewie changes. (00:14:45)
Continuity mistake: The bar owner puts two drinks on the table with olives in them. When it cuts back to the table, Stewie's drink doesn't have the olive in it anymore.
Continuity mistake: Just after Lois says "He's never gonna learn like that", Lois and Peter get much closer between shots. (00:09:50)
Chosen answer: I have seen both versions and no they weren't.
Lummie ★