SpongeBob SquarePants creator Stephen Hillenburg passed away following a fight with ALS, Variety reports. He was 57 years old. “Steve imbued ‘SpongeBob SquarePants’ with a unique sense of humor and innocence that has brought joy to generations of kids and families everywhere,” Nickelodeon said in a statement, according to Variety. “His utterly original characters and the world of Bikini Bottom will long stand as a reminder of the value of optimism, friendship and the limitless power of imagination.”

Before SpongeBob, Stephen Hillenburg filled in as an executive for Rocko’s Modern Life from 1993 to 1996. SpongeBob SquarePants later debuted on Nickelodeon in 1999. The show spawned two films, 2004’s The SpongeBob SquarePants Movie, 2015’s The SpongeBob Movie: Sponge Out of Water, and the Tony-winning SpongeBob SquarePants: The Broadway Musical.

The SpongeBob show and motion pictures highlighted notable artists, including Wilco, the Flaming Lips, Ween, and the Shins, among others. Broadly, David Bowie voiced Lord Royal Highness in the scene “Atlantis SquarePantis.” SpongeBob SquarePants: The Broadway Musical, which debuted in 2016, also included Bowie and Brian Eno’s tune “No Control,” alongside tracks composed by T.I., Panic! At the Disco, John Legend, and that’s only the tip of the iceberg.