The amber citadel - Freda Warrington

Humans share the world with the shape-changing Bhahdradomen, who they defeated in war centuries ago, and the mysterious Aelyr, who keep apart but also consider the Bhahdradomen as enemies.
Now, the shapechangers' wiles inflame a king's madness and lead to war and murder. Two sisters and two brothers from a quiet village are about to be dragged into the conflict, where they will find unlooked-for destinies.

Freda Warrington is the author of the bestselling BLACKBIRD fantasy novels. She has also written dark fantasies, including a sequel to DRACULA which won the Dracula Society's award for Best Gothic Novel. Her novel THE AMBER CITADEL, part of THE JEWELFIRE TRILOGY, was nominated for the British Fantasy Society's Best Novel award. Freda was born in Leicester and lives near Charnwood Forest where she enjoys art, all things Gothic and stained-glass work. For more information, please visit her website on http://members.aol.com/FredaMike/index.html