This is my second book by this author, and so far I've learned that she had a way of presenting a mystery that at first seems to be the most important part of the book as you're reading it becomes almost nonexistence while still being at the forefront of the story.
Vera is from a small isolated town where the mothers are all affected with afflictions that make some of them disappear. There is no real rhythm or reason to who goes or who stays. It could be that they dote on their children too much or not enough. You can't really discern what exactly is happening in that town, are the mothers really disappearing, are they leaving, being taken, who knows, and by the time you finish reading (just like with her first book Saint X) the mystery will never be solved. But you don't really care, you don't really want to know. That's the beauty of it all, that's the beauty of elsewhere.