If you can't have good luck, you should at least have a good dragon.

The princess has inherited the family curse. Plagued by terrible luck, it is all the palace staff can do to keep her safe from herself. When her father pricks himself with an assassin's needle meant for her, her mother Queen Jade knows there is only one thing they can do. They must seek a cure. To reach it, they will need the help of their greatest protector. But even the great dragon Halfax may not be ready for the challenges ahead.

Halfax is a direct sequel to Jade. It takes place many years after the events of the Book of Deacon series.