"She said What??!!"

My four year old is drop, dead, serious about a lot of things.  Some of the things she says are outrageously hilarious, roll around on the ground funny, but never to her.  This afternoon she wanted to make a bus out of a box that the Little One's new umbrella stroller came in.  I told her to use her imagination.  To which she responded..

"Stop talking about my imagination!  I looked already,  I don't have one. OK??!"

Oh.my.word.