A fire fighter is working on the engine outside the station when he notices a little boy next door in a little red wagon with a tiny ladders hung off the side and a garden hose tightly coiled in the middle. The boy is wearing a fire fighter's helmet and has the wagon tied to a dog and a cat. The fire fighter walks over to take a closer look. "That sure is a nice fire truck," the fire fighter says with admiration.
"Thanks," says the little boy. As the fire fighter looks a little closer, he notices the boy has tied the wagon to the dog's collar and to the cat's testicles.
"Little partner," the fire fighter says, "I don't want to tell you how to run your fire truck, but if you were to tie that rope around the cat's collar, I think you could go faster."
The little boy says, "You're probably right, but then I wouldn't have a siren."