I think one of Sweetie's favorite words is "silly". Daddy is silly, she hears people say silly things, she loves to laugh and be silly, and silly knock knock jokes are her favorite things to share and learn.
Anything will do, really. Which makes it easier for her Daddy and I to entertain her.
Sweetie's joke for us:
Potatoes turn into french fries! (she's bursts into hysterical laughter at her own "silly" answer)
Our joke for Sweetie:
Mama Mia, here I go again... (we laugh at our lame attempt at entertaining her. She just continues on, belting out the rest of the chorus "My, my, how can I resist you?" But she's happy.)
Silly girl. Sure do love you. :)