The context of the following conversation is Kai put confetti and streamers all over the house. Kai played a prank on their parents.:
Kai says I played a prank on my parents yesterday..
The friend responds Yeah, what did you do?.
Kai responds I put confetti and streamers all over the house like I was having a surprise birthday party for my dad..
The friend responds But it's not your dad's birthday until September..
Kai responds That's the joke!.
The friend responds You worked too hard on a joke that's not even funny..