Christine Day is an Indigenous American author of children's books. She is a member of the Upper Skagit Indian Tribe. Her novel We Still Belong won the American Indian Youth Literature Award for middle school book, and three of her books have received American Indian Youth Literature Award honors.
Day grew up in Seattle. Her mother was adopted prior to the Indian Child Welfare Act, which inspired her debut novel, I Can Make This Promise.
As a child, she attended a ballet program with Pacific Northwest Ballet School, where she learned about Maria Tallchief. Later, when approached about adapting Clinton and Boiger's picture book about Tallchief, she was thrilled at the opportunity.
Day received a master's degree from the University of Washington. For her thesis, she studied Coast Salish weaving traditions.
In 2019, the Chicago Public Library, Kirkus Reviews, NPR included I Can Make This Promise on their list of the best books of the year.
The Sea in Winter is a Junior Library Guild book. Kirkus Reviews also included it on their list of the best children's books of 2021.