I Said "Duh Duh"

Noah has been getting a little more adventurous lately and climbing on our coffee table to stand on it. Since the little guy likes to jump off and it is very unsafe I tell him to sit down. The only problem is my unhappy face makes him smile and giggle so I am completely ineffective. Well the other day, this happens...

Noah stands on the table and Mommy tells him to "Sit Down" and points down.
Noah smiles and giggles.
Mommy leaves the room and lets Daddy handle it.
Daddy ignores Noah and wont look at him, hoping that he will get bored and get down himself.
Noah points to Daddy and the ground with a stern look and says "Duh Duh".

Needless to say, we are still working on our effective, unhappy face.