Miss Manners

So, i'm really trying to work with Aubrey on her manners. Not just the "please" and "thank you's", but sharing, and waiting patiently, etc. She does pretty well, but her sassiness is starting to come out. So, instead of saying "please" when she wants something, little Miss Aubrey says "Please, now." Ummmm.... what am I supposed to say to that?!?!?