Io'i is the elder sister of Blue Jay and, unlike him, a figure of knowledge and restraint. In the central narrative she is given in marriage to a man of the dead and goes to live in the ghost-country, and it is to reach her that Blue Jay makes his journey there. Throughout the cycle she supplies the correct understanding of events that her brother lacks, warning and instructing him even as he blunders. Her steady wisdom against Blue Jay's folly gives the Chinookan cycle its characteristic pairing of a sensible woman with a reckless man.