In which year, did this earliest guest star in 1999 for SpongeBob SquarePants stop providing the voice?
Mermaid Man and Barnacle Boy Mermaid Man and Barnacle Boy are fictional superheroes in the Nickelodeon animated television series "SpongeBob SquarePants". Mermaid Man was voiced by Ernest Borgnine from 1999 to his death in 2012, and Barnacle Boy is voiced by Tim Conway. Mermaid Man and Barnacle Boy were created and designed by Stephen Hillenburg. The characters debuted on August 21, 1999 in the series' episode "Mermaid Man and Barnacle Boy".
Muppet Babies Jim Henson's Muppet Babies, commonly known by the shortened title Muppet Babies, is an American animated television series that aired from September 15, 1984 to November 2, 1991 on CBS. The show portrays childhood versions of the Muppets living together in a nursery under the care of a human woman called Nanny. Nanny appears in almost every episode, but her face is never visible, only the babies' view of her pink skirt, purple sweater, and distinctive green and white striped socks is shown. The idea of presenting the Muppets as children first appeared in a dream sequence in "The Muppets Take Manhattan" (1984), released two months before "Muppet Babies" debuted, in which Miss Piggy imagined what it would be like if she and Kermit the Frog had grown up together.