Children of Poseidon are automatically in line for a throne in one of the Atlantean city-states, something that has not happened since before the Oath of the Big Three. Since then, Atlantis has rallied under one king with only a few scattered cities ruling independent. Thus was King Orin's rule. Percy is the first Poseidon child to be born under these new circumstances, though it doesn't matter. she has no desire to rule, and she was already in line for the throne anyway. I don't own you can't sue and you should know the rest of the rhyme by now