Boo's humans said his heart literally broke after the death of his best friend, Buddy.
Tragic Boo the Pomeranian 'hung on for a year' after pal's death
World's Cutest Dog': Boo the Pomeranian dies of 'a broken heart
World's cutest dog Boo cutest photos gallery
Fans Mourn The Death Of Boo, Pomeranian Known As 'World's Cutest Dog
Dog Fanatics
Boo the Pomeranian dog dies 'from a broken heart' - BBC News
Dog Fanatics
This decade taught us to love viral pets. Now we have to grieve
Samoyed Dogs Are Basically A Breed Of Big, Fluffy, Sentient Clouds
Advantech MFG (@AdvantechMFG) / X
Boo the Pomeranian dead 'World's Cutest Dog' dies of 'broken heart