The shark son is the son of the shark dad who makes his only appearance in the episode "Sportz?"
He is a short shark, with red shorts and braces.
When SpongeBob and Patrick are racing with ice skates on, the shark son asks if he can play as well. However, the shark dad says that they are sports fans, and that they watch instead. The shark dad then pulls up a chair and the son puts on a foam hand, as they both watch SpongeBob and Patrick.