The Curse of Chalion is Lois McMaster Bujold's fantasy novel printed in 2001. You might remember Bujold from her series about Miles Vorkosiagan, who was a physically-impaired spy and mercenary admiral. It was a great series.
This newer book, The Curse of Chalion, is about a land whose rulers have been cursed to live harmful lives. There are many twists turns and weaves in this story. First you meet a man, Cazaril, who comes home as a begger and is given as a tutor to the princess. In the background, you learn of her mother who is quite insane. The grandmother has been taking care of her daughter and trying to keep her grandson and granddaughter away from the politics that surround the king.
The king is the older half-brother to the pair and is also old enough to be their father. The kin is unable to have children... And so the story goes--
Also, Bujold has taken a lot of time and effort in explaining the country's religion. Take interest. It will all be explained in the conclusion. I had to go back and reread certain parts to make sure I understood the politics of religion and state.
Bujold deserves kudos for this very interesting, and very intricate book. It is in my library so that I can reread it.