She likes to have her "say" in matters. My crazy old bat! I just posted the entire series for you since you seem to be reading them so FAST O_o Granted they're short. Book One is the longest Book four is only VERY short. But don't read them out of order, it'll be confusing otherwise, they all tie in together.
Hope you like it, Sonja is at her peak in Book III
I hope you like them.