Dragonkeeper 5: Shadow Sister  (English, Paperback, Wilkinson Carole)

Tao is learning to be a dragonkeeper. With no one to teach him it is not easy. He must keep Kai safe but there is danger at every turn - they are pursued by a gang of murderous nomads, tricked by unseen spirits, attacked by a giant seven - headed snake and disoriented in the realms of the dead. Most terrifying of all is the ghost who can turn blood into ice. Tao knows he must prove he is truly worthy of the name dragonkeeper. But the road west is never straight and nothing for Tao and Kai is what it seems.