Lois-Ann Yamanaka

Behold the Many is the eerily beautiful story of three young sisters, Anah, Aki, and Leah. In 1913, they are sent away from their family for treatment for tuberculosis to an orphanage in Hawaii's Kalihi Valley. Of the three, two will die there, in spite of the nuns' best efforts to save them, and only Anah, the eldest, will grow to adulthood.
But the ghosts of the dead children are afraid to leave the grounds of St. Joseph's, which is

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"Claire sees lava, sandy beaches, and undersea coral reefs on her island of Hawai'i. Yet she dreams of snow falling from the sky, snowflakes melting on her tongue, and most of all, building a snowman. See how Claire's dreams become 'real' as she learns to appreciate the island she call home."--Provided by publisher.