When the man came home, his wife was crying.
“Your mother insulted me,” she sobbed.
“My mother? How could she do that?” the man asked. She’s on vacation on the other side of the world!”
“I know. But this morning a letter addressed to you arrived. I opened it because I was curious.”
“And?”
“At the end of the letter it was written:
‘PS. Dear Diane, when you have finished reading this letter, don’t forget to give it to my son.'”