wide mouth frog

Not sure why, but lately at dinner Cooper starts openeing his mouth really wide and saying "yaaaaaaaaaah" at me from across the table. But he squints his eyes close at the same time. hmmmmm....not sure at all what thats about but it sure is funny!
Here is a video of it: http://s57.photobucket.com/albums/g234/mwalsh36/?action=view&current=October132006309.flv

The boys and girl watching a show.