Knock, knock.
Orphan: Who's there?
Not your parents!
Knock, knock.
Orphan: Who's there?
Not your parents!
Listen up, you chucklehead! This joke is funny because it's dark. The orphan says "Who's there?" and the joke teller responds that their parents are not there. Haha! You see, orphans do not have parents because their parents are dead, which is sad. But it is funny. Sad-funny. You are probably an orphan because of how dumb you are.