"Cat into a Prince" joke

An old lady is rocking away the last of her days on her front porch, reflecting on her long life, when--all of a sudden--a fairy godmother appears in front of her and informs her that she will be granted three wishes.
"Well, now," says the old lady, "I guess I would like to be really rich."
*** POOF ***
Her rocking chair turns to solid gold.
"And, gee, I guess I wouldn't mind being a young, beautiful princess."
*** POOF ***
She turns into a beautiful young woman.
"Your third wish?" asked the fairy godmother.
Just then the old woman's cat wanders across the porch in front of them.
"Ooh--can you change him into a handsome prince?" she asks.
*** POOF ***
There before her stands a young man more handsome than anyone could possibly imagine. She stares at him, smitten. With a smile that makes her knees weak, he saunters across the porch and whispers in her ear: "Bet you're sorry you had me neutered."