Stephen Hillenburg: ~ $120 Million

You may not know Stephen Hillenburg by his name, but you have definitely seen his most famous animated cartoon character, SpongeBob SquarePants! Before he created the famous animation series, he was animating for other Nickelodeon shows such as Rocko’s Modern Life and The Green Beret, while attending art school. SpongeBob became such a huge hit, after being dubbed in many different languages, and made its creator very wealthy. It also made children aware of marine life and hence, Stephen also became a marine science educator. Unfortunately, he died in 2018 due to a degenerative disease, and he was worth $120 million then.