Why Poseidon claims Percy as his son?

Poseidon claims Percy as his son because Percy Jackson is a demigod, the mortal offspring of a god and a human. In the context of Greek mythology, Poseidon, the god of the sea, is proud of his son, recognizing Percy's potential and bravery. This paternal connection not only grants Percy unique powers related to water but also places him in the midst of significant conflicts in the world of gods and monsters, highlighting the ongoing legacy of divine lineage.