Why do you think Cassie’s strategy of getting Wordell to talk to her worked?

One day Cassie sees Wordell alone and gets enough nerve to talk to him. She tries talking about music after asking him if he’d seen her brothers. Wordell is silent. She asks him if Joe is his best friend and Wordell’s expression softens. Cassie talks on, saying she likes Joe even though he is slow, and then remembers the time at the belfry. Suddenly she has an epiphany that Wordell did not do anything to Doris Anne, but actually protected her and covered for Joe. Wordell says nothing but picks up his axe. Cassie is scared and tries to run away but trips and falls. Wordell looks at her and says her brothers are by the stream. Cassie runs away, grateful to escape. Later she realizes it was the first time he’d ever spoken to her.