Beyond the Bright Sea by Lauren Wolk

Twelve-year-old Crow has lived her entire life on a tiny, isolated piece of the starkly beautiful Elizabeth Islands in Massachusetts. Abandoned and set adrift on a small boat when she was just hours old, Crow’s only companions are Osh, the man who rescued and raised her, and Miss Maggie, their fierce and affectionate neighbor across the sandbar.

Crow has always been curious about the world around her, but it isn’t until the night a mysterious fire appears across the water that the unspoken question of her own history forms in her heart. Soon, a chain of events is triggered, leading Crow down a path of discovery and danger.