Biologically based personality traits such as reward and punishment sensitivity, and family factors, such as maternal dysfunctional eating and parental alcohol abuse, have been linked to hazardous drinking and disordered eating. However, specific relationships between personality and family factors in the development of these disorders are still unclear. A total of 443 women completed measures of reward and punishment sensitivity, family environment, maternal eating and parental drinking. Reward sensitivity was directly associated with both dysfunctional eating and drinking. Punishment sensitivity was associated with dysfunctional eating but not hazardous drinking. Punishment sensitivity mediated a chaotic family environment and daughters' dysfunctional eating. It is suggested that reward and punishment sensitivity are key traits to examine when investigating vulnerability to risky behaviour. Future research into disordered eating is likely to be advanced by an active search for mediators and moderators of family risk.