Three Old Sisters

Three old sisters, 92, 94, and 96 years old respectively, all lived together. One day the oldest drew a bath. She put one foot in the water, paused, then called downstairs to her sisters,

"Am I getting in the tub or out of the tub?"

The middle sister started up the stairs to help, then paused on the landing, and called back downstairs,"Was I going up or coming down?"

The youngest sister, who was sitting at the kitchen table having a cup of tea, said, "I guess I'll have to help. I hope I never get that forgetful!" and knocked on wood. She got up, then paused, and called, "I'll be up as soon as I see who's at the door!"