SpongeBob SquarePants features a truly wacky setting and cast of characters. As a result, the Nickelodeon series can stretch believability for the sake of an episode or a joke. What makes it work is that the characters themselves remain firmly rooted in their personalities, which highlights their endearing qualities.

One of the show's oldest relationships is between Mr. Krabs and his daughter Pearl. Ever since the first season of SpongeBob SquarePants, fans have speculated about Mr. Krabs' lost wife and Pearl's mom, and what happened to her. But it's one mystery that will likely never be solved -- as it was the express intent of creator Stephen Hillenburg to never feature the character. Why did he want to leave the audience in the dark about Mrs. Krabs?

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What Happened to Mrs. Krabs on SpongeBob SquarePants?

SpongeBob SquarePants Mr. Krabs Pearl Mom 3

Pearl was introduced all the way back in Season 1, Episode 8, "Squeaky Boots." The teenage daughter of Mr. Krabs, Pearl is a version of the "Daddy's Princess" archetype. She's one of Mr. Krabs' very few soft spots and a friendly presence in the show -- albeit one whose perspective and desires often clash with SpongeBob and everyone else in her orbit. According to publications like Makin' Toons: Inside the Most Popular Animated TV Shows and Movies and Nickelodeon Magazine, Pearl was among the earliest characters developed for the series, inspired by Hillenburg's time working at the Ocean Institute in California.

Ever since her debut, however, fans have speculated on her true origins. Mr. Krabs is a crustacean, while the massive Pearl is a whale. Pearl's mother has been referenced periodically over the years, but has never appeared on the show. All that's known about her is that she is a whale like her daughter and had been married to Mr. Krabs -- although it's unclear if she separated from the Krusty Krab owner or if she passed away. The latter has been a consistent question about the show since its earliest days, and that's what Hillenburg wanted.

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Why Mrs. Krabs Will Never Appear in SpongeBob SquarePants

SpongeBob SquarePants Mr. Krabs Pearl Mom 2

SpongeBob SquarePants executive producer Vincent Waller has addressed the Mrs. Krabs mystery on his Twitter account. According to Waller, the question of Mrs. Krabs came up in the writers' room and an episode dealing with her absence was pitched and outlined as a possible entry in Season 5. However, ultimately turned down the concept, arguing that it was funnier if Pearl's mother never appeared on the show. Even after Hillenburg's passing that idea has carried on, and Pearl's mother hasn't even surfaced on spinoffs like Kamp Koral: SpongeBob's Under Years, though that series is a prequel and would make sense as a place to introduce her.

Pearl's mother will therefore presumably remain one of SpongeBob SquarePants' longest-running unsolved mysteries. That does add a fun minor layer of comedy to Mr. Krabs and Pearl's relationship and allows Krabs a more openly vulnerable side where his daughter is concerned. It also plays into the quietly tragic side of the character, which gives Mr. Krabs a bizarrely dour backstory as a veteran dealing with a shattered family -- history that contrasts hilariously with his more comical elements. It's probably for the best that Mrs. Krabs has never been seen, as it's unlikely she could satisfy the expectations of fans who've been waiting two decades to find out more about the character.