Knock Knock!
Who's there?
Bart.
Bart who?
Bart up the wrong tree!
Knock Knock!
Who's there?
Bjorn.
Bjorn who?
Bjorn with a silver spoon in his mouth.
Knock Knock!
Who's there?
Thaddeus.
Thaddeus who?
To be or not to be, Thaddeus the question.
Knock Knock!
Who's there?
Blue.
Blue who?
Blue away with the wind!