When Jane entered the house, she saw Jon and Zoe in the living room. She was shocked to see that Zoe had changed.
Zoe wasn't Goth, but more than that, she wasn't even a girl. The 14-year old boy sitting in the living room looked a lot like Zoe, but he was definitely a boy. He wore a black T-shirt, blue jeans, and a pair of sneakers. In fact, he dressed very similarly to Jon. They both even had the same somewhat-messy hair.
Apparently, the stone didn't just make them get along with each other. It changed Zoe so that she would have more in common with Jon, so then they would get along with each other.