Boo, the incredibly adorable Pomeranian who became an internet sensation, died in his sleep Friday, his humans announced. He was 12 (in human years).
Often referred to as the world's cutest dog, Boo garnered a massive following on his Facebook page over the last decade. He was the subject of several books and other merchandise. As of Friday, his page had more than 16 million likes and followers.
His older brother Buddy, who was similarly cute and famous, died in 2017.
"With deepest sadness I wanted to share that Boo passed away in his sleep early this morning and has left us to join his best friend, Buddy," his owners wrote on Facebook. "We know that Buddy was the first to greet him on the other side of that rainbow bridge, and this is likely the most excited either of them have been in a long time."
According to his humans, Boo started having heart issues after his brother died.
"We think his heart literally broke when Buddy left us," they wrote.