This slip up occurs during the middle of the movie. Ceci is being dropped off by her father on Sunday night and runs toward her mother, who swoops her up and hugs her tight.

Rewind to the scene where Ceci is running from the car toward her mother. She has a blonde haired doll in her left hand. Mid-run she switches the doll to her right hand. As her mother lifts her and hugs her, the doll disappears from her right hand and as she's being set down, the doll reappears in her left hand.