Continuity mistake: Stewie forces Lois to breastfeed him, and she undoes her shirt. As Brian and Lois argue about who is going to test her milk, Cleveland barges in and is shot. When Lois jumps up, her shirt is buttoned again, with no time for her to do it.
Continuity mistake: When we first see the English guy in his car, his crates of goods are stacked askew in the back seat. After Peter's crew shoot the car several times and the car is half-wrecked, the boxes are suddenly neatly packed into the seats. Moments later, we see the boxes piled randomly again. This change happens a couple more times before the scene is over.
Continuity mistake: The English guy's car is full of crates when we first see it and when his roof is blown off but after Peter and a crewman have boarded, there are suddenly barrels in the car too.
Blue Harvest - S6-E1
Continuity mistake: After Vader (Stewie) kills Obi-Wan, Luke yells out and then the shot shows storm troopers firing at him with Vader in the background. Vader's lightsaber is blue, when it should be red. It is red in the previous and next shots. (00:34:00)
Continuity mistake: In the scene when Peter tries to get the bullfrog out the window there is a dartboard but when he walks in it wasn't there.
Continuity mistake: The bullet holes in Lois keep changing place between shots. This also happens during the flashback in the courtroom.
Continuity mistake: The kitchen sink is completely missing. It has always been in front of the window through the entire series. (00:01:40)
Continuity mistake: Stewie puts the gun and pictures in a bag and throws them in the trash can to get rid of the evidence. When Joe takes the lid off, he just reaches in like Stewie had put them in there separately and not in a bag.
The Former Life of Brian - S6-E12
Continuity mistake: While talking to Brian about Jared's mom, his face is painted up as a cat. After the cut scene to the Pink Panther, Stewie's face is suddenly clean.
Continuity mistake: The scene where Lois is on the boat and Stewie is shooting her, the bullets are going through her body and out her back and in some shots you can see exit wounds on her back but in other shots they're missing.
Continuity mistake: Meg comes in the kitchen and Peter pulls out her chair for her. Next shot of Meg shows a plate of food appear out of nowhere. Peter, Lois and Chris had a plate in front of them and there was no plate in front of Meg at any time. There was no other food in sight on the counter or stove either. (00:15:00)
Blue Harvest - S6-E1
Continuity mistake: When Obi-wan (Hebert) stars singing, Luke (Chris) is holding his stormtrooper helmet. About a quarter into the song, there is no sign of the helmet Luke was holding.
Continuity mistake: After Peter has a stroke, later on he asks Lois for a beer. She gets it from the fridge and gives it to him without opening it yet he immediately takes a drink and spills it on his shirt.
Answer: Lacey Chabert was the actress who originally voiced Meg in early episodes. She left of her own accord due to being in school and other acting work; Seth MacFarlane has stated there was no tension with her leaving, but it makes for a handy joke for the show.
Jon Sandys