Birk - The Ember Town Series, #3

Nymphs are female-or so Birk's mother has always insisted. But after a conversation with Lucas, Birk finally found the language to express their true identity: they are non-binary, and at least one nymph isn't female. When Birk is unexpectedly outed, they're cast out of the only family they've ever known. Alone in Ember, a town they've lived in but barely interacted with, Birk faces a world that suddenly feels much larger and far more intimidating. Separated from their tree, which holds their soul, and with almost nothing to their name, Birk must learn how to survive.
But in Ember, there might just be a new family waiting for them-one that accepts them for exactly who they are.