During the shooting sequence, Lois' bullet wounds move around from scene to scene. When she is first shot, the bullets pierce the middle of her chest. During the slow motion scene, however, the wounds are fewer in number and more spread out, plus there are wounds on her shoulders. Thought the bullets obviously pierce her body, the moment she falls overboard, no exit wounds are visible on her back, though they appear as she is shown falling from the ship. When she is underwater, the exit wounds disappear again.
When Stewie is holding a drawing of Lois tied to a rock drowning, there's a piece of the rope in between her legs. When Joe's holding the picture, the piece of rope is missing.
At Peter's trial, Meg is shown with her hat on in a long shot. In the very next shot, a closeup, Meg is not wearing the hat.