Plot hole: When the kids barricade themselves in the basement, Brent and Kendall try to cut through the door, but Josh fends them off with a pistol he stole from his dad. After that scene, though, the pistol completely disappears from the plot; Brent and Kendall don't consider it when they try to gas the children out, and neither kid appears to have it after they escape into the house.
Continuity mistake: When Nicholas Cage and his kid are enjoying a flashback, the ice lolly keeps shrinking and growing throughout the conversation. (01:14:00 - 01:15:00)
