Stephen Hillenburg, the creator of SpongeBob SquarePants, has passed away. He was 57.

SpongeBob SquarePants debuted on Nickelodeon in the late 1990s and quickly became a huge hit. Besides his work with SpongeBob, Hillenburg also wrote and directed episodes of Rocko’s Modern Life.

Hillenburg is survived by his wife, Karen, and his son, Clay, according to TMZ.

[TMZ]