Shadows Over London by Christian Klaver
The Faerie have come to take London, and only one girl stands in their way.
Justice isn't your average fifteen-year-old girl. She's an irrepressible scoundrel, and she always has a plan. But her world falls apart when her father forcibly bundles the entire family into carriages in the middle of the night and carts them off to a strange mansion on the outskirts of Victorian London. The Faerie are invading, but the Kasric siblings can't stay neutral in the ensuing war when they find their parents on opposing sides. Justice has no choice but to embrace her burgeoning magical powers to fight against the Faerie and save her family.