Continuity mistake: At the start Ed has a blue shirt on. He leaves the house with his son - when he turns to wave goodbye the shirt has turned grey.
Other mistake: When the son is going to the potty, you hear him peeing but there is no stream of urine.
Other mistake: When the police arrive at the house the marked police car had Ardsley Police on the side. The other vehicle was unmarked. Charlie tells his mom it's NYPD before the detectives come into the house and introduce themselves. (01:34:00 - 01:35:00)
Snag.1
Answer: There is no significance, the script just says it is a "little doodle".
Sierra1