User blog comment:SayuriDarling/Full first chapter of The Mark of Athena/@comment-186.120.51.200-20120628011148/@comment-3323804-20120701015328

I think the root of the fight(s) between Jason and Percy will probably stem from leadership issues rather than minor aspects of their life and personality. I also wouldn't necessarily say Jason is the leader of the Prophecy of Seven. Based on The Lost Hero, and the hints about Jason's life, I would say he's a strong leader, whereas we know that Percy is a strong leader based on the past series and The Son of Neptune.

Another base of a fight could also be the difference in culture.