Son of Poseidon?
Percy Jackson isn't who you think he is. For on thing, he isn't actually a he. He, is a she. Percy Jackson is Transgender . A girl trapped in a boys body. When she comes out to the camp, she is shunned because of what she is. Feeling abandoned, Percie leaves camp to her moms house, only to find her dead. In her hand, she finds a piece of paper, telling her that Poseidon is not her father by blood, but her adopted father. Leaving the apartment for the last time, Percie takes to the street, only to be found by Hestia.
Disclaimer: I do not own Percy Jackson and the Olympians, Marvel, Heroes of Olympus, or Norse Mythology.