Jon had bumped into his little brother Mikey. But how would a "gender swap chain" react to touching someone of the same gender? As it turned out, there was no reaction. Jon and Mikey were both male, so both of them remained male.
But even if Jon was now "safe" from any future effects of the swap chain (he technically swapped, so now he couldn't swap again, since he was the start of the chain), his little brother wasn't. The next person that Mikey touched would swap genders with him. And whatever gender Mikey became, he'd be stuck that way for the rest of his life.
Mikey headed downstairs to watch his usual before-school cartoons, until his mother finished making breakfast.
