Call of the Crow (Skyborn #2)

Jessica Khoury brings her masterful world-building and emotional depth to this soaring fantasy series. In a world where everyone is born with wings, stone monsters prowl the skies, hunting those who dare to fly too high.

In the Clandoms, everyone is born with wings, though not all the clans are treated equally. Ellie Meadows longed to become a Goldwing―the knights who protect the people―but because she came from the humble Sparrow Clan, her dream faced almost insurmountable resistance.
Nox Hatcher has it even worse. Nox is a Crow, a shattered clan. They can't own businesses or run organizations, all due to mysterious betrayal made hundreds of years ago. Nox has had to steal and scrape just to survive, but a single goal has kept him going, even when it felt like all the Clandoms were against him. Years ago, his mother was imprisoned for a crime she didn't commit. Now, finally, Nox is going to save her.
But there’s more to Nox’s story than even he realizes, a secret that’s been kept buried for centuries. And the king of the Clandoms himself is so desperate to conceal it that he’s sent a ruthless assassin after Nox and his friends.
The four young fugitives must watch every shadow. If they aren’t careful, they’ll be cut down before they can rescue anyone .