Perdix

Perdix was the nephew of Daedalus and a cousin of Icarus.

History
The old master was jealous of the boy's genius which rivaled his own and one day, in a rage, caused his nephew to lose his balance and fall to his death. Athena saw what he had done and swore to make him pay, then and forever more for his part in the boy's death.

When Perdix died, Athena turned him into a small partridge. She then branded Daedalus with the image of a partridge for his crime, a murderer's brand.

The Battle of the Labyrinth
Percy was many dreams in the labyrinth and eventually sees the death of Perdix. In his dream, Daedalus passed an object to Perdix, but Perdix went to far and went over the side of a balcony which Daedalus had planned to happen. As Perdix hung on, Janus, God of choices and doorways, appeared in the sky as Daedalus was faced with the choice of saving Perdix or letting him fall to his death.He let Perdix fall to his death and Athena appeared before Daedalus and eternally punished him by placing a mark on his soul that would never go away and appear on any body he was inhabiting (Daedalus found a way to cheat death by transferring his soul to an automaton). He also got the idea for an automaton body from Perdix, but made a few modifications over the millennia. He killed himself after the Battle of the Labyrinth was over, gave Percy Jackson Mrs. O' Leary and Annabeth his laptop and files.

Trivia

 * Perdix, a species of Partridges, is named after him.
 * As he is not a demigod himself but descended from one, this would make Perdix a Legacy of Athena.