The stone answered Zoe's question in a voice that sounded like the voiceovers from the opening credits of 50s sitcoms. "Your mother is now your father and your father is now your mother."
"Duh ..." said Zoe. "I already knew that. Does 'your' mean just mine?"
"No, Jon's too - in the same sense as yours."
"What's this 'sense' business?"
"Your parents adopted you from South Korea - just as they adopted Jon from Haiti."
"That's why I don't sound 'black'," said Jon. "I was raised by whites." It felt strange to think of his parents as ... different from him. "But if our parents are still together, why couldn't they have biological children?"
"Well ..." started the stone.