"Some days are grumpier than others," Grumpy Cat's publicist said in a statement on Friday, sharing news that the internet's favorite meme star has died.

Grumpy died Tuesday morning of complications related to a urinary tract infection, the cat's publicist said. She was 7 years old.

Grumpy Cat, whose real name was Tardar Sauce, became an internet sensation after a photo of her trademark frowning face went viral on Reddit in 2012. Since then, she became the subject of countless memes, a Honey Nut Cheerios commercial, book deals and even a Lifetime movie.

She had more than 8.5 million Facebook fans, 2.4 million followers on Instagram, 1.5 million followers on Twitter and more than 260,000 subscribers on YouTube.

The famous mixed-breed feline died "peacefully" in the arms of her owner, Tabatha Bundesen, the statement said.

In past interviews, Bundesen described her famous cat as actually the opposite of grumpy: "She's very sweet and docile."

The cat had a form of dwarfism that caused her downturned mouth, huge blue eyes and small size.

"Grumpy Cat has helped millions of people smile all around the world — even when times were tough," the statement said.

Contributing: Jocelyn McClurg. Follow Ashley May on Twitter: @AshleyMayTweets