User blog comment:Menara/Bianca di Angelo may be one of the 7/@comment-3193220-20110908230935/@comment-3498371-20110909101237

People assume that Hazel will be the child of Hades but I don't think so since we already saw in earlier book that horses don't like Nico as he smells of Death. So the child of Hades/Pluto is still unknown. (I'm sure Frank is a child of Mars)