We lost a special little soul on Sunday - Harley, Northern Colorado's "Hero Dog."

On Sunday evening, a friend of Harley's mom and dad - Dan and Rudi Taylor - made a Facebook post on Harley's behalf to announce he had taken his last breath on earth.

"He went on his own terms ... he chose his moment, he did not suffer, and he was not in pain. He passed away peacefully surrounded by the love of his mom and dad," the friend wrote, who identified herself as Mary. "This is not the end. As today is the first day of spring - a day of new beginnings - let this be a new beginning in the fight against puppy mills, and let Harley's voice be heard through each and every one of us."

Harley the chihuahua spent the first 10 years of his life in a puppy mill, and was recognized as 2015's "Emerging Hero Dog" by the American Humane Association last fall. He and the Taylors, based in Berthoud, Colorado, made frequent appearances to educate the public on the misfortune and mistreatment of mill dogs through the National Mill Dog Rescue.

Harley, we thank you for all you have done for not only mill dogs, but all animal-kind. You will be so greatly missed, but your legacy and message carry on!