Smiley, the blind therapy dog whose tragedy-to-triumph story caught global attention, said a final goodbye on Saturday.

In a Facebook post, his owner Joanne George said she made the decision to euthanize Smiley after two tumours were found on the dog's stomach and liver.

"Today is the day I give Smiley back. It's time. He's had enough. I do this for him, he doesn't deserve any suffering," she wrote on Twitter. 

smiley's buddy

"A boy and his dog must part ways eventually," reads a tweet captioning this heartbreaking image from Smiley's Twitter account. (@Mysmileydog/Twitter)

George rescued the golden retriever who was born with a condition causing blindness from a puppy mill over 10 years ago. 

Since 2010, Smiley has helped countless people as a therapy dog with the St. John Ambulance (SJA) Therapy Dog program. Many of those showed up to a candle-lit vigil for the beloved dog Sunday in his home town of Stouffville.

 "I hope he is running free and can finally see the beauty around him. I hope he was met by old and new friends. His heart was so big he was able to share it with the world," Smiley's owner Joanne George wrote.

Smiley's death has prompted an outpouring of support from his hundreds-of-thousands of online followers. 

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