My good friends Anna Kudak and Carol Bruess published a book called, "What Happy Couples Do" - based on research Anna did during her master's program at NDSU on rituals.
My parents were interviewed for Anna's thesis and are featured in the book under the heading "Back Scratch to Basics" using pseudonyms.
Quote from the book (using my parents real names):
For the past twenty years or so, Hassan has been scratching Mayla's back as she falls asleep at night:
"It's the best thing to go to sleep and relax with someone scratching my back. Each night around nine o'clock, I climb into bed and turn to Hassan. 'Okay, now it's your time to scratch my back.'"
Well, about 3 years ago, my dad almost lost his arm to a rare infection. Well... we almost lost him. He was in the hospital for six weeks. Six surgeries and 11 large incisions to his arm later... he was back home.
One of the things my mom told Anna was that she had thought - "Hassan won't be able to scratch my back anymore." And how much she would miss that.
So the first night my dad was back from the hospital... guess what happened?
My mom says as she was falling asleep she opened her eyes to find him standing on her side of the bed, scratching her back with his good arm.