The streak of filling that Rachel spills on Carl's apron suddenly changes from smooth to smeared.
Just before Rachel says, "Let's not waste our energy fighting," there are only about three filled tarts on the the tray in front of her. After cutting to a close-up of Rachel saying the line, and then to a longer shot, almost all the tarts are filled without Rachel having had time to do so.
Just before Rachel comes in with the news about the restaurant, Carl and Harriet are standing up. In the next shot, as Rachel comes in, they are both sitting down in the same chair.
The kids are home from school on Monday morning when the tarts are delivered, with no explanation for their absence.