Because she didn't have any arms. Knock knock. (Who's there?)...not Sarah.
Aw shucks!
A flat miner.
Someone threw a fridge at her. It's not supposed to make sense
Q: Why did Sarah fall of the swing? A: Because she has no arms. Q:Who's there? A:Not Sarah.
Because she has no arms! Knock knock. Who's there Not Susie!
No, cows go moo.
Because it wasn't big enough to be a Buck.
Because she had no arms. Knock-knock! "Who's there " Not Sarah.