Jokes / "Daddy, I want to get married!"

A boy says, "Daddy, Daddy, I want to get married!"

The father says, "For that son, you have to have a boy and a girl." 

The son says, "I've found a girl." 

"Who?"

"My grandmother." 

"Let me get this straight,"the father says. "You want to marry my mother? You can't do that."

"Well, why not?" the son says. "You married mine!"