characters go away
I have said here in various places (and no doubt you've heard this from other writers and teachers of writing) that a serious storyteller can't afford to mollycoddle characters. Sometimes, of course, a writer or a director will really push the envelop on this. Think (if you can make yourself) of Andy Sipowitz on the once wonderful NYPD Blue, who has had spouses, best friends and children die by violence, cancer, and mishap; he's had cancer; he's fallen off the wagon a multitude of times. Who can bear to watch? Think of John Crichton (much more rewarding) of Farscape, who really has had some rough times, enough that a worried group of his devoted watchers began a Society for Prevention of Cruelty to John Crichton. Apparently Ben Browder, who plays John Crichton, wears that t-shirt now and then.
In comparison, I don't think I've been all that bad to my characters. In the normal course of things they've had some rough times. They aren't immune to disease, warfare, broken hearts. I'm going somewhere with this, maybe you've guessed.
It occurs to me that readers might be surprised about (1) who has gone away for good in the interim between Lake in the Clouds and Fire Along the Sky and (2) who goes away, for good, by the end of Fire Along the Sky. By my quick count there are six major and quite a few minor characters who make their departure. I'm hoping readers won't be too upset. Just to forestall a flurry of worried emails: neither Nathaniel nor Elizabeth die or are injured in any serious way.