The Whispering Woods. The Hollow Crown, #2

The first relic has been claimed, but the cost was higher than any of the heirs imagined. With the Mirror of Echoes now a heavy weight in Prince Corwin's pack, the siblings must plunge deeper into the heart of the Whispering Woods to find the second relic: the Cinder Heart. But the woods are alive, fueled by the same corruption that took their father's mind. As the trees shift and the paths vanish, the heirs are haunted by auditory hallucinations-voices of the King that pit brother against sister.
With the Warden's hounds nipping at their heels and Eira's survival skills pushed to the limit, the group must decide if they are willing to burn the past to survive the night. In the Whispering Woods, the greatest threat isn't the darkness outside, but the secrets that refuse to stay buried.