Seven months among mermaids and devils and sprites

My niece dropped a handful of maple keys into a small pool of tea-colored water dappled brightly with leaves in a hollow of the grass and said something about fairy skates. I have since learned that she has been building fairy houses out of twigs etc. with the nearer set of twins. Her personal mythos appears to be expanding.

Does anyone have recommendations for fairy books or media that might appeal to an almost eight-year-old who likes dragons, unicorns, selkies, and mermaids but does not just sit down and read her way through the complete bibliography of Katharine Briggs? My immediate instinct was to show her FairyTale: A True Story (1997), because I was reminded of a scene in it, but she may be slightly too young for it yet. She already has my copy of Cicely Mary Barker's Flower Fairies of the Seasons (1988), but otherwise I got such fairies as I had in childhood almost entirely from books of folklore and Barrie's Peter Pan in Kensington Gardens (1906), the first American edition with the Rackham illustrations inherited from my great-grandparents; my mother reminds me that I also read her childhood copy of Kingsley's The Water Babies (1863) because I missed all of the racism and satire and went straight for Mother Carey. We have things like Jane Yolen and Charles Mikolaycak's Tam Lin (1990) and Eric Quayle and Michael Foreman's The Little People's Pageant of Cornish Legends (1986) lying around the house and she probably would enjoy Alan Lee and Brian Froud's Faeries (1978) if I could get my copy out of storage. She has the tolerance for eerie images of a child who grew up annually watching The Nightmare Before Christmas (1993), but I can't always tell what she will find narratively scary.

I have done little with fairy themes in my own work: a couple of recurring motifs. It would not have been shocking for changelings to be important to me, but I fastened onto other kinds of nonhumanness instead.