Isaiah likes to punctuate nearly every statement with "You know dat?". The man who picked us up at the hotel to go to the rental car place got to hear a nearly line-by-line synopsis of the Monsters vs. Aliens movie - with lots of "You know dat?" included.
I've started telling him things and following up with the same question. Then I tell him I know that because he told me so and he knows it because I told him so.
Oh.... what a revelation to him.
You know dat?