Camp Half-Blood: Hades' Curse

Solaris and Aidan were raised by the same foster parents, both of which they had presumed to be their blood-parents, only to discover that they were solly related through their biological mother, whom had disappeared when they were born. Solaris uncovers the truth behind her real father, the Greek God, Poseidon. Her brother, however, his blood heritage came from a much darker presence. Accused of being a sort of Anti-Christ, Aidan is driven out of the only home he'd ever known, only to be followed by his sister. Now, It's up to her to get him to safety, before something bad happens to him...