A young man was walking through a super-market to pick up a few things when he noticed an old lady following him. "Excuse me," he said. "Can I help you?" "Oh, Pardon me," the old woman replied. "I'm sorry if my staring has made you uncomfortable. But you look just like my son. He died recently and I never got to say goodbye." "I'm very sorry," replied the young man. "Is there anything I can do for you?" "Yes," she said, "as I'm leaving, would you say 'Goodbye, mother?' It would make me feel so much better." "Sure," answered the young man. As the old woman was leaving, he called out, "Goodbye, Mother!" Then, as he stepped up to the checkout counter, he saw that his total was nearly $200. "How can that be?" he asked. "I only purchased a few things!" The clerk replied, "Your mother said you'd pay for her."