The Ocean's Second Son-A Percy Jackson Fanfic

Percy and Annabeth settle down at Camp Half Blood to enjoy their senior year in High school together.
Camp Half Blood and Camp Jupiter are forming an alliance. The Greeks and Romans have let go of years of silly conflict and joined forces to create a large army of Godlings. Demigods can visit the opposite camp, train with them, and are free to interact with both Greek and Romans.
Everything is going great.
Except for Alex.
He lives in Salzburg, Austria. He has ADHD, and is constantly seeing and hearing unnatural things. All his life, there was always something screwed up. He lives with his mom, a kind lady who is sadly not home often and stepdad, who is a jerk, lazy, and is a drug addict.
What happens when Alex and Percy meet, and Alex finds the answers he has been waiting his whole life for?