The Wind Singer by William Nicholson is somewher between Fantasy for kids and YA. As I’m not the target audience, my opinion can’t serve as a good recommendation.
I found it a fairly ok fairytale, complete with good vs evil, strong patterns, but no strong character decelopment; with a strong internal logic that didn’t make sense when looking at it in any other light than that of a fairytale. Strong siblings vs the rest of the world, humanity vs bureaucratic dystopia, all very good patterns, and a decent-enough execution, but not something that felt particularly important to me. I can’t say how I would’ve liked it as a kid, but I probably would’ve read it just like I read a ton of Fantasy: entertaining in the moment, then merging into a vague memory of all the other somewhat generic Fantasy arcs.