User blog comment:Menara/The Son of Sobek: The official PJ and Kane Chronicles Crossover/@comment-5593616-20130515180205/@comment-122.167.23.62-20130516072358

Either Annabeth survived or Percy got over her death and can control his emotions like Reyna. I mean, look at him, he doesn't show much sense of humor and initially treats Carter harshly. Throughout the story, he is rather serious and at the end, he turns calm. So yeah, either Tartarus changed him or he must've gotten over Annabeth's death.