Jon's Always Been A Girl?

"I wish Jon was a girl," Karyn said. Then the stone emitted a strange purple glow. Jon immediately morphed into a nearly-naked female version of himself. Karyn looked around as if she were in a daze, then looked over at *Jen*, who was holding a bath towel around herself, at waist level. "Karyn! What did you do to me?" "What are you talking about?" "You turned me into a girl!" "But, you've always been a girl." Jon was speechless, but also confused. How come she didn't remember how things were supposed to be? And why did the stone glow purple instead of white?