Jon was his own cousin - and half-brother

Jon bore a strong resemblance to his old self. He had become the son of his mother's sister. Reality had changed itself as little as possible to accomodate Crystal's newfound youth. Up until now, Jon's aunt had been single. Now she had been married to their father for almost twenty years. Her sister's children Jon, Zoe, and Mikey were now *her* children. But her parents were too old to be Crystal's parents. So who were her parents now? And what excuse did she have for having been in Jon's room in the new reality?