When the house turns haunted at the end, the girls look in all the rooms to find Ginger and her parents. But all the rooms appear to be the same, just changed slightly.
Mr Whisping sets the girls up for their sleepover in the rumpus room of the house, which appears to be located upstairs and has a single door. However, at the end of the film, when the girls come out of the room, it is located downstairs and has a double door.