for Maiden of the Mist by Veronika Martenova Charles
Long ago, a Seneca tribe lived on the Niagara River, just upstream from a great waterfall. With plenty of fish and crops to feed them, life was good in their village. Then a sickness came to the people, and everything changed. As the situation worsened and people died, Lelawala, the chief's daughter, came up with a plan to help. She would go to the thunder god, Hinu, and find out why he wouldn't help her people. But to do that, Lelawala would have to go to his home under the great falls, and never return.