The Maine Coon Cat was surrounded by family when it happened on Monday, his owner Robin Hendrickson told the Reno Gazette Journal. He was eight.
Stewie was declared the longest domestic cat in the world by Guinness World Records in 2010, measuring a total of 48.5 inches from the tip of his nose to the tip of his tail.
The cat lived a life of service. According to the RGJ, Stewie was a certified therapy animal that frequented one of Reno's senior centers and helped promote animal welfare awareness with the Nevada Humane Society.
“Stewie was always very social and loved meeting new people,” Hendrickson said. “He has touched many lives, and for that I am grateful.”
Stewie was diagnosed with Lymphosarcoma, a malignant disease of the lymphoid tissues, in early 2012, but he was declared cancer-free after undergoing chemotherapy. Unfortunately, the feline's remission period didn't last long and he was later diagnosed with another tumor on his kidneys.
“I knew that although we could fight it, the end was near and so I wanted to simply make him comfortable and let him enjoy the time he did have,” Hendrickson said.
The Guinness World Records has not reveled who will succeed Stewie as the world's longest cat.
For more photos of Stewie visit his Facebook page.