When celebrities pull stupid faces part 12,8593

Whenever J-Lo goes in front of the photographers she always does this stoned-out, slack jawed expression. It’s almost as irritating as Keira Knightley’s pout.  Why do celebrities pull such silly trademark faces?  The narrowed, sleepy eyes that look like they can’t take the weight of her fake eyelashes and the parted lips just begging for a stream of drool to emerge… not a good look.  She’s so much prettier when she smiles.