When a brain tumor took away Dorothy Holm’s ability to speak, she picked up index cards and began filling them, edge to edge, with seemingly random, indecipherable sequences of letters. Her grandchildren saw her scribbling and thought she was leaving them a code — but it was one the preteens couldn’t crack. 18 years later, her granddaughter posted a notecard online asking for help. Within 13 minutes the mystery had been solved. Click here to read Dorothy’s final thoughts!