It was chance that brought Clara Daly and Tim Cook together. It was an act of kindness that brought their story to the attention of millions. They found themselves on the same flight to Portland, Oregon - Clara, 15, with her mother, Tim, 64, alone. Tim is deaf and blind, so airline staff - unable to communicate with him - made an announcement asking if any passengers knew sign language. That's when Clara, who has been learning American Sign Language (ASL) for a year, came forward. The teenager spelled out words using ASL onto the palms of Tim's hands, allowing him to feel the letters.