The issue of Cousin BlackJack’s size has been a source of contention for fans of the show since its inception. Some attribute the character’s diminutive stature to budgetary constraints, while others argue that his size is purposely minimized in order to maintain a sense of comic book realism.
Regardless of the reason, it remains one of the more confusing aspects of SpongeBob SquarePants.
One potential explanation for Cousin BlackJack’s small size is that he is actually a child; in the episode “The Lost Treasure of Spikini Bottom,” it is revealed that he is only about 8 years old. This would explain his relative lack of muscle and stature, as well as his propensity for getting into trouble.
Another possibility is that Cousin BlackJack is actually an inch or two shorter than SpongeBob, due to him being made from rubber rather than flesh. This would also explain his smaller stature, as rubber does not naturally grow in size.
Regardless of the reason for Cousin BlackJack’s diminutive size, fans continue to debate the issue online and at conventions around the world. As with all things related to SpongeBob SquarePants, no definitive answer will ever be provided.