One day little Johnny is in his backyard digging a hole. His neighbour, seeing him there, decides to investigate.
"Whatcha doin?" he asks.
Johnny replies, "My goldfish died and I'm burying him."
"That's an awful big hole for a goldfish, ain't it?" asks the neighbour, smiling condescendingly at the youngster.
"That's because," snaps Johnny back, "he's inside your f*cking cat!!!"
Funny boy fish burial joke