Bonsai had Sacral Agenesis (Caudal Regression), a disease only found in humans. He was born with half a spine, no pelvis, and immobile hind legs.
No one expected Bonsai the bulldog, who was born with only half a body, to live long, but his owners and fans around the world were devastated when he died last weekend. He was only 16 months old.
Read: Rescued English Bulldog Born with Half a Body Will Melt Your Heart
In an emotional Facebook post, his rescuer Elizabeth Hart explained: "We've always been aware that Bonsai may not live a long life due to his rare combined conditions — he hadn't been sick, there was no warning, and we are still shocked at the sudden happenings."
Bonsai was born with a series of rare deformities, including half a spine, no pelvis, and tiny, immobile, hind legs that were later amputated since they were causing him pain.
But, she wrote that the bulldog lived a relatively healthy life before he passed away quietly in the middle of the night: "I tucked him into his little bed as I do every night. A few hours later, I heard what sounded like a faint cough, little bark, and then nothing. His heart had stopped, just that quickly."
Born to an Arkansas breeder in April 2015, he was surrendered to a Texas rescue organization, Friends of Emma, founded by his rescuer Hart, when he was only 3 and a half weeks old.
Hart told InsideEdition.com in a previous interview that Bonsai had Sacral Agenesis (Caudal Regression), a disease only found in humans, until Bonsai's diagnosis.
For that reason, Bonsai was quickly named the official mascot for the International Sacral Agenesis/Caudal Regression Association (iSACRA).
Read: Meet Mojo, the Elderly Short Spine Dog Who Is Stealing Hearts Across America
Not only did he inspire and support humans suffering from the same condition, his social media presence under the name "Half a Bulldog, Twice the Love" quickly racked up a slew of followers.
"He was so loved. I can hardly believe he is gone," one of his supporters wrote on Facebook. "Run free Bonsai, you left so many broken hearts behind."
Watch: Dog Grieves for 21-Year-Old Owner Killed in Car Crash: 'It's as If He's Looking for Someone'
