Continuity mistake: At the top of the mountain, there are 3 string of flags attached to a pole. The shortest of which is 3 flags. Red, Blue, Yellow. However, after the shot zooms and comes back to the Griffins, the colours are now Blue, Red, Blue. The colours of a second string also change. (00:13:30)
Continuity mistake: Just as the Griffin's start down the mountain the flags disappear from behind them. (00:14:30)
Continuity mistake: The colour of the ropes tying the ladders together changes from white to yellow. (00:11:00)
Continuity mistake: When the guys are arguing over the trophy Quagmires teeth disappear for 10 seconds. His mouth is all black then they reappear.
Continuity mistake: When Lois opens the door to Peters mum, Peter appears at the door and Lois simply vanishes. (00:05:00)
Continuity mistake: When Lois is talking to Brian about having homicidal thoughts, the rug colours swap order. (00:14:20)
A Very Special Family Guy Freakin' Christmas - S3-E16
Continuity mistake: When Brian is in the kitchen with the oven fire and an empty fire extinguisher, the side door behind Brian has its door handle on the right side, but when the family returns and Lois opens that door, the handle is on the left side of the door.
Brian: Portrait of a Dog - S1-E7
Continuity mistake: While Peter and Brian are arguing in the kitchen the side door has a handle on the right side, but when Peter insists that Brian use the leash Brian storms out of the house, and the door's hardware has changed to a doorknob that is now on the left side of the door.
A Very Special Family Guy Freakin' Christmas - S3-E16
Continuity mistake: When Stewie's nightmare wakes him up, the crib's headboard is decorated with a crescent moon and two stars, but when Stewie goes bananas and searches for the wire, the stars and crescent moon have vanished.
A Very Special Family Guy Freakin' Christmas - S3-E16
Continuity mistake: When Lois asks Brian to put on his sweater the rabbit ears antenna is atop the TV, but when Lois asks Peter to "please" get the tree, the TV antenna has vanished then it reappears, and the rug isn't where it should be then it too reappears properly.
A Very Special Family Guy Freakin' Christmas - S3-E16
Continuity mistake: When Lois reminds Peter to go get the tree, there's a wreath with a bow hanging on the wall between the two pictures behind the couch, but when Lois convinces Peter with the promise of a new VCR that wreath has vanished, then it reappears and disappears again when Peter returns with the tree. Also, the plate of cookies that are on the arm of the couch seem to vanish as well.
Continuity mistake: After Peter says goodbye to his family before his flight to Ireland, when it cuts to Stewie spying on Lois while she's doing the dishes, there's a calendar hanging on the wall beside the refrigerator and a paper hanging on the fridge, but when Stewie draws on the wall both the calendar and paper have vanished.
Whistle While Your Wife Works - S5-E5
Continuity mistake: When Lois is helping Peter get his work done while he has the hand injury, Peter gives Lois the flip book to proofread. During this scene the phone power cord appears then disappears, and the door knob as well as the kick plate vanish then reappear properly.
Continuity mistake: Peter goes to see his mom. She's drinking coffee and puts the cup down on the table to answer the door. In the next shot the cup disappears.
Continuity mistake: As the trio are singing at the end, the position of the 3 changes between instant cuts. (00:20:05)
Continuity mistake: Going up the ladder Lois has Stewie in her left arm. However, as she comes through the window he is in her right arm. (00:06:00)