In a long picture story, a young girl, Olivia, and Mingo, the family slave, watch the sea throughout the seasons to see if the low tide will lay bare Aunt Becky’s Ledge. Mingo tells the child that her grandfather had promised him his freedom if that ever happened. As much as Olivia honors Mingo’s wish, she wants him to stay. In a parallel, one day she finds a baby mockingbird and Mingo shows her how to feed it and keep it alive. Mingo tells her she’ll have to keep it safe until it can fly away, but Olivia doesn’t want to let it go, either. Mingo tells her, “. . . someday you’ll know that keeping another soul caged is wrong.” Many years later, Mingo falls ill and on the day he dies, Olivia is able to walk to Aunt Becky’s Ledge carrying the bird. When she reaches the ledge, she sets the bird free and thinks she hears the song “Swing Low, Sweet Chariot,” the song she had sung with Mingo, free at last. Oil on canvas illustrations give a sweep to the landscape; the backgrounds are hazy and almost abstract, highlighting the human figures that seem stiff and posed. An author’s note relates that this was a legend in Pride’s Crossing, a section of Beverly, Massachusetts; her research includes the archival records of Mingo that she found in the Beverly Vital Records. In the author’s note, she explains that she created Olivia to make it possible to tell the story and includes a short description of slavery in Massachusetts. Sentimental, but it will find its audience. (Picture book. 7-9)