Swapper Slide: back to normal?

Heading into Jon's bedroom, Jon picked up the small wooden box and took the stone out. "Okay" said Jon, "Lets fix things." Clutching the stone, Jon made a wish, "I wish we were swapped back to normal." There was a bright flash from the stone, and Jon and Karyn were forced to look away. Looking back they saw what had happened. "Crap" Said Jon, in Karyn's voice. The wish had swapped them back to normal, but instead of swapping their crotches, it had swapped the rest of their bodies to match up. "Jon, you've gotta fix this" panicked Karyn, speaking in Jon's voice