Andy Griffith and Don Knots shared a famous chemistry visible on The Andy Griffith Show right away. That came, in part, from earnest friendship built up over the years. However, when Don Knotts was dying, he didn\u2019t want to be seen - even by his dear friend. So, Griffith channeled Sheriff Andy Taylor. Very few people actually knew Knotts was so ill. Fewer knew just what he was ill with: cancer. It left him needing an oxygen machine to breathe. As a result, he felt humiliated and didn\u2019t want to be seen in such a state. But Griffith wanted to be there for his colleague and friend. Andy Griffith learns his best friend Don Knotts was dying Don Knotts and Andy Griffith shared a friendship that transcended work \/ Everett Collection \u201cDon told almost no one of his illness, lest news should leak to the tabloids,\u201d wrote Andy and Don author and Knotts\u2019 brother-in-law Daniel de Vis\u00e9 in 2015. \u201cDon still wanted to work, and a sick actor could not get work. He didn\u2019t tell his children he was dying. He didn\u2019t tell Andy.\u201d RELATED: Why Andy Griffith Worried Don Knotts Wouldn\u2019t Go To Heaven That illness started as pulmonary fibrosis, a diagnosis he received when he was 80. Even with his lungs gradually increasingly out-of-commission, Knotts continued to work. In fact, he did voice work for 2005\u2019s Chicken Little. He also brought back the role of landlord Ralph Furley from Three\u2019s Company for That \u201870s Show. However, Knotts would learn even more sobering news that he was essentially dying from lung cancer. Griffith and Sheriff Andy Taylor help Knotts When Griffith feared Knotts dying alone and scared, he channeled a move from Sheriff Taylor to connect and comfort \/ Everett Collection It was 2005 when Griffith, Knotts, and their wives enjoyed dinner together. At that dinner, Griffith knew something was wrong. Griffith tried inviting Knotts to a holiday event, only for Knotts to reply, \u201cIt\u2019s not a good time; I don\u2019t think I can fit it in.\u201d He received some insight from Knotts\u2019 wife Francey, who \u201ctold him that Don was having lung trouble, and that he was reluctant to tell anyone or be seen with his breathing aids.\u201d She did not specify Knotts was dying from cancer, out of respect for his wish for privacy. However, Griffith wanted to still connect to his dear friend and offer comfort. Just like Knotts had his breathing equipment, Griffith countered, \u201cLook, I have my little scooter that I sometimes drive around the house. I don\u2019t like people to see me on my scooter. I\u2019ll have my scooter, and you\u2019ll have your oxygen.\u201d At this, the two laughed. Then, Griffith assured, \u201cWe\u2019re going to get through this.\u201d It\u2019s written that the gesture allowed Knotts to end the talk looking \u201cimmeasurably relieved.\u201d Ultimately, Don Knotts passed away on February 24, 2006. His famous friend, Andy Griffith, died on July 3, 2012.