Yesterday Wisconsin resident John Unger said goodbye to his best friend, a 20-year-old shepherd mix named Schoep.

“I Breathe But I Can't Catch My Breath...” Unger wrote on his dog's Facebook page, which has almost 200,000 followers. “Schoep passed yesterday. More information in the days ahead.”

A photo of Unger rocking his dog to sleep in Lake Superior went viral last year, and Unger credits the outpouring of support they received for helping Schoep live another year.

Schoep had gone blind from cataracts and suffered from arthritis and hip problems. He also had trouble sleeping.

John Unger and his dog SchoepTo ease his pet’s pain and help him sleep, Unger regularly took Schoep to Lake Superior. The water was therapeutic for the ailing dog’s joints, so Unger would hold Schoep in his arms and rock him to sleep.

Last August, photographer Hannah Stonehouse Hudson, a friend of Unger’s, decided to capture the moment. She posted the photo to Facebook, and the image — and Schoep’s story — spread across the Web.

Letters of support, as well as thousands of dollars, soon poured in from around the world. Unger used the more than $25,000 in donations to pay for weekly laser therapy that stimulated cells in Schoep’s body. Helping the cells reproduce faster reduced swelling and pain.

The therapy improved the old dog’s quality of life and allowed him to live another year, a gift that Unger continually gives thanks for on Schoep’s Facebook page.

Watch a video of Unger and Schoep below.

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