What is the theme in Tooth & Nail: An Inspector Rebus Novel by Ian Rankin?

Child abuse is a major theme in the book. The Wolfman grew up in the home of parents who were alcoholics. The father often became angry and violent toward his wife. The mother often belittled her husband, calling him names and ridiculing his appearance. The mother was an artist, a bad artist, who believed art to be her calling. Whenever someone would attempt to point out that her art was bad, the mother would become abusive, belligerent, and lash out. This included her own husband and her child.