Continuity mistake: After the Robert Redford clip, when it cuts to the Griffins walking toward Doug's house, in this exterior shot (and a previous exterior shot) the front door is located between one window and the garage, but in the following interior shots there's a window on both the left and right side of the front door. (00:14:20)
Continuity mistake: After the LASIK surgery Lois has bandages covering her eyes, and the pairs of crisscrossed tape switch their over-under positions within the same shot.