Pomeranian turned social media star, Boo, known as the "world's cutest dog," has died of a broken heart, according to his owners.
He was 12 years old.
In a post on Boo's Facebook page, which has over 16 million fans, "Boo's humans" wrote that Boo passed in his sleep in the early morning hours of Jan. 18.
They believe he has gone on to join his best friend, Buddy, who died in 2017.
"Shortly after Buddy died, Boo showed signs of heart issues. We think his heart literally broke when Buddy left us. He hung on and gave us over a year. But it looks like it was his time, and I’m sure it was a most joyous moment for them when they saw each other in heaven," they wrote.
Known for his teddy-bear-like appearance, Boo had his own line of plush toys modeled after him, which are produced by toy maker Gund. He also was the subject of four picture books.