Mikey (still with Jon's personality) looked down to see two breasts and realized whose body he had. "I'm Mikey," he said. "I have your body, don't I?"
"It appears that you do," Karyn (in Zoe's body, with Leonard's personality) said. She peered around the room, taking stock of the situation.
She saw Leonard crying. A moment ago, he had been yelling. And from how he was talking, Karyn surmised that he was actually Sarah.
Sitting nearby was Sarah's body, but it was presumably inhabited by the now-childish Jon, since most of her actions seemed more like those of Mikey.
She looked around some more and spotted Jon's body. But since Jon had Sarah's body, who could it be? She walked over to him and shook him awake.
"Who are you?" Karyn asked him.