I discovered the book through a post by Anderson in the Speculative Faith blog. Anderson tells more about herself, and her writing, in that post.
Now to my post: the book is well written, and seems to have been written from a Christian world-view, but that world-view is not at all intrusive. The library where I got the book has it classified as for older children.
I'll start with the setting. Bryony is a faery, apparently in the UK. She is looking out a window in the tree she lives in, and sees a young human boy, climbing the tree. He sees her, too.
The small group of faeries, all female, live in a centuries-old hollow oak. She is the youngest of the group. They have lost most of their magic, and they are afraid to go outside the oak's bark. They don't seem to do anything for each other out of generosity, or love, just as a re-payment for some work done for them, or for other favors. Hunters and gatherers have to go out, to collect food and other raw materials. Bryony becomes a Hunter, by edict of the Queen. Her weapons are primitive, and not always effective, mostly because the faeries have no supply of steel. There is a human house, not too far, or too close, to the oak. Bryony goes there, and is able to enter the house, and to take a small knife-blade from a woodcarving set. She asks the Queen to name her Knife.
I will not give away the plot any further, except to say that Knife eventually learns much of what has made her group of faeries so small, unable to reproduce except by leaving an egg behind when they die, and so fearful.
Christian world-view? The faeries have a deity, The Gardener, and breathe prayers to him (?) when in great need. In spite of what I said about their seeming selfishness, above, there is a lot of unselfish sacrifice in the book, and by more than one faery. And the book ends with acknowledgments, and finally, this quotation: