Is there a future when characters are frozen into their past?

Today I get to invite one of my favorite authors of paranormal and science fiction, Christine Amsden. She's the author of lots of books that I've read and loved, but her latest is another in the Cassie Scot Paranormal Detective series - a continuation of a series that (almost) seemed finished. Since I'm working on one series and dreaming of another, it seemed like a good idea to ask her, over virtual coffee, how she ended up with Cassie Scot starring and co-starring so many times, and how do...