Jon really was in pain and crying for real, but he also knew that for a little girl to cry would get a lot more sympathy than a teenage boy. "Mom... he hit me with my own rock! I tried to take it back and he hit me!"
"There, there, Joan," said Joan's mother, and handed her the rock.
Joan quickly whispered a wish. "I wish I was unhurt, alone in my room, and I wish Mikey forgot about the rock."
Once Joan disappeared from the car and reappeared in her newly pink room, she thought a bit and made another wish. It might be possible for Joan to become her correct age. Mikey had wished that he and Jon trade ages. He can't undo it--but exactly what was "undoing"?
"I wish that Mikey and I still traded ages, but that now, after the trade, we once again become the ages we were yesterday." That should do it. The trade still happened--he and Mikey just changed a second time, after the trade.
Jon realized, as his body grew, that he was changing. He seemed to be male--mostly.
"I wish I knew why I'm like this."
The voice rang in his head. "The wish you would be a little girl is still in effect. In order for you to be your previous age, and still be a little girl, you are now a little girl--the same way you can be a little hungry or a little tired."
Jon was his teenage self, but he was, indeed, a little girl--that is, a little bit girl--because he was male except for....
