Meg Rosoff

Daisy is a spoiled American teen with plans to spend the summer in England with her aunt and cousins at their farmhouse. While her aunt is away, an unnamed country invades England, and soldiers take over the farmhouse. Lacking adult guidance, Daisy must stop thinking of herself and take responsibility for her young cousins. This novel won both the Printz Award (U.S.) and the Guardian Children's Fiction Award (U.K.).