The Eternal Night Saga Book 1: Evening Star

Cyrus and his sisters, Phoebe and Lucille, have no idea who their parents are. The only thing known is that his father had left them with their present guardians, Devin, Shauna, and their son RJ, ten years ago, then mysteriously disappeared. When a mysterious letter from their mother appears, the three of them try to investigate. What they find, though, is far from anything they could have imagined. Soon after, an ancient evil rises and casts the world into the darkness of an endless night, Lucille gets kidnapped by the armies of the dreaded Vampire King, and on top of that, Cyrus discovers he holds a power he never knew he had. Will this bizarre turn of events bring him any closer to the answers he's been desperately asking for all his life? Cyrus knows only that there is a chance that he will fail, and even if he succeeds, he and his small family will be irreversibly changed.