The Ingalls family packs up their covered wagon and travels from the big woods of Wisconsin to a new home in Kansas Territory, where wide open land stretches as far as the eye can see. On the prairie, they build a house, meet neighboring Indians, build a well, and fight a prairie fire.

Eight-year-old Cassie Witting is upset when she finds out that her mother, Sarah, is expecting a baby, but writing in the journal that was her brother Caleb's helps her sort out her feelings and she finally learns that Sarah will always love her.