**spoilers** Heir of Fire. Can some explain what is going on with Terrasen and the royal family?

I just started Heir of Fire. I understand Celeana is the missing Terrasen princess and rightful queen. The royal family was murdered but she got away.

Now she is in Wendlyn and it is being ruled by her cousin? Is that correct?

Why didn’t she go to her cousin for help in the 10 years she was free? I feel like l missed something in books 1 and 2.