The grandfather clock that the baby turtles flies into and smashes has numbers from 1-13. They should be in 1-12, since there are 12 different hours per AM/PM for the total of 24 hours per day.
The baby turtles flies into the grandfather clock and gets smashed, and Dexter has a memory in his head about Dee Dee confronting him over breaking their mom's grandfather clock. Their mom should be aware of the incident and talk to her kids about the damage being done and owing her for repairs or a replacement.