When Kate DiCamillo’s characters talk, she listens. And so do we. During a visit to St. Louis this summer, the two-time Newbery Medalist shared the story behind her most personal novel yet, “Raymie Nightingale.” And she revealed the reason behind her new novel, “Louisiana’s Way Home,” which expands the story of Raymie’s best friend, Louisiana Elefante. “This voice of Louisiana just would not go away,” said DiCamillo, who, in two decades of writing, has never revisited a story until now. “She just was so insistent, and I thought, ok, I’m going to tell this story.” In this 30-minute interview, DiCamillo talks about the characters who’ve shaped her life, the gift her mother gave her, and why she still can’t believe she get to do this.