A random note:
I recently read Susan Ee's Penryn trilogy and I have to say that Penryn's mom is a really fascinating character. In fact, a book from her point-of-view would be interesting, and I'm not sure I've ever wished I could read from the main character's mom's point-of-view before.
P.S. If you only read the first book, what I've said above won't make much sense to you.