Barbara Vetter is the mother of Det. Tracy Vetter, Nick's partner in the third season. Like her daughter, she is fair: they even wear similar hair styles. On the whole, she and Tracy get on all right. "Mum's okay," is the way Tracy puts it. In the episode Avenging Angel, we learn that she and Tracy's father Richard are getting a divorce, which Tracy blames on her mother's alcoholism. Barbara ascribes both her drinking and the divorce to her husband neglecting her in favour of his career.