I loved all three books even though they were quite different. All are about families and how they shape us. Part of this theme is that families may be those whom we assemble around us rather than those related by blood.
In "The Secret Language", both Connie and Faith have suffered damage and serious neglect at the hands of their parents, Billy and Delle, traveling actors who were semi-famous but never achieved the fame they sought. These were people who really loved only themselves and the idea of who they were, and their two pretty little girls were part of this image.
The strong coping mechanisms that the sisters developed as children helped them then and continued to help them in adulthood. Unfortunately, the way that Faith coped was to try to avoid feeling too deeply. Despite having married into an outgoing family, the Dohertys, Faith has been walled off for so long that she is unable to connect and always feels like an outsider....they seem overwhelming to her. She seems incapable of allowing Joe to love her, and feels as if she is frozen and incapable of being any other way. Her sister Connie also fears love, but in a different way.
When Isadora appears and wants to be let into their lives, to be an instant sister, she does not realize she will never really be on the inside because there are no shared experiences. She will never see their father, Billy, for the narcissist whom he was, caring only about himself and the image he projected. Like Billy, Isadora is also self-absorbed and a user who will do almost anything to get her way. To say that she is manipulative is an understatement.
I really appreciate the way Wood develops her characters. As a reader, I feel that I know these people: feel their pain, their joy, their sorrow. What a gift!