If you're like the average lot of us, who can't get enough of watching cute dog videos on social media then you must know, Boo, the 12-year-old Pomeranian.

This smol ball of joy was known as the world's cutest dog and rightly so. But, alas, this is a sad day for all of us Boo admirers.

His owner announced on Friday that Boo passed away in his sleep, at age 12.

"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."

With a massive following of 540K on Instagram and over 16 million likes on Facebook, Boo was the sweetheart of social media.

Boo was known to bring smiles to hearts laden with the burden of daily chores. The owner said that Boo was the happiest dog he'd ever met.

"Boo brought joy to people all over the world. Boo is the happiest dog I’ve ever met. He was so easy going that we never had to bother with training."

Boo was a natural. His big googly eyes melted hearts in a jiffy.

His hoomans believe that when Boo's brother, Buddy, passed away, this poor thing's heart 'literally broke'.

"Shortly after Buddy died, Boo showed signs of heart issues. We think his heart literally broke when Buddy left us."

BRB, gonna go ugly cry now.