10 of those

Aderyn pushed through the press of people, searching for her brother and finding him at last in their dwelling, ransacking his chests and filling a leather bag with his things. He meant to defy their father, then. 

Despite an invading threat from the south and his father’s refusal to let him go, Leif abandons his twin sister in search of the mysterious lights that fell from the sky one snow-covered night. As Leif’s desperate longing for answers drives him on, back at home Aderyn grows increasingly close to an injured prisoner of war, but can this stranger really be trusted?