The Dragons Among Us (Book 5) Daughter of the Alchemist

"Held captive by the Alchemist tribe controlled by dragons, Noah finds his long lost sister, who is now an alchemist and worshiper of dragons. He must save her or die trying. But she has no interest in being saved. Worse still, the ruthless enemies of the Alchemists, known as Scalers, seek to destroy Noah and the tribe of Alchemists who have taken him captive. Noah's only hope now is to find the Silver Dragons who once helped his father, Jack, overcome the darkness." -- from teddekker.com.