The internet pet sensation fondly known as Grumpy Cat died Tuesday morning aged 7.
The famous feline's owners announced her death on social media early Friday.
"We are unimaginably heartbroken to announce the loss of our beloved Grumpy Cat," wrote Tabatha, Bryan and Chrystal Bundesen in a statement.
The mixed-breed “encountered complications from a recent urinary tract infection that unfortunately became too tough for her to overcome,” the statement read.
“She passed away peacefully,” it added, “at home in the arms of her mommy, Tabatha.”
The family from Morristown, Arizona, noted how Grumpy Cat, whose real name is Tardar Sauce, had “helped millions of people smile all around the world - even when times were tough.”
It vowed that “her spirit will continue to live on through her fans everywhere.”
Tributes poured in on Twitter, where fans said they were “heartbroken” by the news.
Grumpy Cat became an online star as a kitten after this photograph that Bryan Bundesen shared online of her looking very grumpy indeed went viral.
Her purported displeased look became a popular meme on social media.
She had 8.5 million Facebook fans, 2.4 million on Instagram, 1.5 million on Twitter and 264,000 YouTube subscribers. She endorsed Friskies cat food and had a book series published in her name.
She appeared in Broadway musical “Cats,” and inspired and starred in the 2014 Lifetime movie “Grumpy Cat’s Worst Christmas Ever.”
She had an animatronic figure made in her honor by the Madame Tussauds waxworks museum.