Vashti Harrison burst onto the children’s book scene with her book, “Little Leaders: Bold Women in Black History.” But to hear her tell it, Vashti still cannot believe that her entry point for kidlit was through nonfiction. Perhaps that is why she took such care and tenderness in creating her first fictional picture book, “Big.” In “Big,” we meet a young girl whose journey feels universally relatable, even if her story is uniquely hers. The book earned Vashti many accolades, including the Caldecott Medal and the Coretta Scott King Award. But its profound effect on her personally was also a great gift and illuminating force for Vashti.