A husband and wife decided they needed to use a code word to indicate that they wanted to have sex, without letting their children in on the idea, so they decided on the word "typewriter."
One day, the husband told his five year old daughter, "Dear, go tell your
mommy that Daddy needs to type a letter. "
The child went into the next room and told her mom what Daddy had said, and
her mother responded, "Honey, tell your daddy that he can't type a letter right
now because there's a red ribbon in the typewriter."
The child went back to tell her dad what her mom had said.
A few days later, the mother told her daughter, "Honey, go tell Daddy that he
can type that letter now."
The child went into the next room and gave her dad the message. A few moments
later, she returned to her mother and announced, "Daddy said never mind with the
typewriter, he already wrote the letter by hand."