Barbara has a secret friend who lives in the garden. It’s her twin sister, Lalla-Lee, and Barbara doesn’t have to share her with her papa or mama or brother. What’s even better is that Lalla-Lee calls Barbara her “Most Beloved Sister.” Together, the girls bravely ride their horses through the Great Horrible Forest, where the nasty Frights live, to visit the Kind Ones in the meadow. The Kind Ones always give them cookies and caramels. And best of all, Barbara and Lalla-Lee go to the Most Beautiful Valley in the World, where the trees and the flowers sing. At the end of this particular adventure, Barbara knows that she must say goodbye to Lalla-Lee for the final time. But when she arrives home, there is a wonderful surprise waiting for her.