When Emmie Button's big sister, Hannah, transforms into a magical creature, Hannah must rely on her unicorn-loving little sister to help her. Will the sisters find a cure for transformia unicornis before sunset, or will Hannah be stuck as a unicorn forever? Emmie and the Accidental Unicorn is filled with sparkles, rainbow puke, and hijinks, but at its core, it's a story about the bond of sisterhood.