When David says goodnight to Emily on the first day in the new house, presenting her the diary, he is wearing a green sweater, but when he leaves the room, he is suddenly wearing a gray one.
When David enters the first bathroom, the tub has foggy sliding doors, but after he opens them they disappear and the empty track guide can be seen.
In the scene after Emily's father gives her the new diary, in an exterior view of the house there is no vehicle. However, when Emily is walking towards the woods, there is an SUV.
Elizabeth's scarf changes position when she enters Emily's room.
The position of the knife in David's hand when he covers his eyes & starts counting "one one thousand, two one thousand" changes between camera shots.
When Emily is laying on her bedroom floor, she draws a picture of her and Charlie at the window, but she draws herself with blonde hair, the actress's natural hair color.