Hugues, I have read the "Thea Thories before", but it was a long time ago. Now that I just re-read it, I didn't know the author thought that Princess Kara was the daughter of Thea, but now that I think about it - the resemblance is uncanny. They look almost identical!
Thanks for providing that; it's a good read, and really thought-provoking for anyone who wonders what the heck happened to Thea during Nial's quest, and who that mysterious Ryan character is.