PHOENIX — Rowley's story starts like many shelter dogs. Lost. Rescued. Waiting.

For months, the 7-year-old Pit Bull terrier remained at the Arizona Humane Society searching for a home. Then a medical emergency gave him an opportunity no one could have predicted.

When a critically ill rescue Pug named Tilly arrived needing an emergency blood transfusion, Rowley became the donor who helped save her life.

The act of kindness gave Tilly a second chance, and not long afterward, Rowley got one, too.

ABC15's Cameron Polom met the rescue dog whose greatest contribution came before he ever found a family, proving that sometimes the pets waiting the longest still have the most to give. Watch the full story in the video player above.

Their story highlights a critical time of year for the Arizona Humane Society. Summer is AHS's busiest season, with thousands of sick, injured, and homeless animals arriving through its doors. Through its Urgent Summer Fund Drive, donations are being matched to help provide lifesaving medical care, emergency treatment and second chances for pets just like Rowley and Tilly.

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