Enlightenment — Laurie Ryan

When Earth cries for help, he must answer or perish.
 
First, he betrayed her. Now he has to let her go. Again.
 
For Kaiden Darcy, duty is everything. As True-named protector, he's tasked with the safety of his home and of Rianthe Royan, the prophesied one designated to save Earth from surrendering to the darkness.
 
Except Rianthe's powers are stifled by some unknown cause. She needs help, so she follows a cryptic clue seeking insight. As she struggles to master her magic, the brother she raised from a babe disappears.
 
Kaiden, realizing the urgency of Rianthe's quest, leaves his own responsibilities behind to go in search of the boy, unaware that search will bring him face to face with bad blood. Family blood. His blood.