Zoe Who?

Mikey walked downstairs to find his mother making breakfast. A few minutes later, he watched Jon walk downstairs, still dressed and made-up just like his sister Zoe. Astonishingly, he also had a nose ring, which Mikey didn't see earlier. "Jon," Mikey's mother said. "Remember to come straight home after school." "Whatever," he said, on his way out. Mikey snickered. It was still funny seeing his brother act that way. He wondered what his sister would think. And speaking of his sister, where was she? "Did Zoe already leave for school?" Mikey asked his mom. "Who?" she asked. Mikey looked at her oddly. "Zoe. You know, my sister." "*Jon* is your sister, Mikey. Who's Zoe?" Mikey's eyes went wide. What happened? Was this some sort of side effect of his wish? He never wanted Jon to *replace* the person he borrowed clothes from. But that's what was happening. What happened to Zoe?