Where does she come up with this stuff?

Today I'm trying to put Isabella down for her nap and she's being a absolute booger.  So I finally get her to lay down in her bed and I'm sitting on the floor beside her.  I have one hand laying flat, palm down on her pillow.  She is holding it with both of her hands and fidgeting with my fingers etc.  I have my eyes closed (hoping to encourage her to do the same).  I hear her breathing change as if she's stifling a laugh.  I look at her to see what's going on and see that she's positioned her head so that my pinky is IN her nose!  I scolded her because that's disgusting, but had a really hard time not laughing.  Seriously, where does she come up with this stuff???