What is the author's style in Unless by Carol Shields?

Shields writes in a linear way, starting with Norah's disappearance and ending with her return to the family. Interwoven throughout the text are Reta's reminisces about her life and her daughter. The novel relies primarily on her thoughts about events in her life, rather than on the events themselves. The primary focus is Reta even though the novel is centered around Norah. Shields gives virtually no physical descriptions of her characters and leaves their general appearance and personal style up to the reader's imagination.