We focus on these putative environmental measures because they are frequently reported to be heritable (Kendler and Baker 2007; Button et al. 2008), they are prevalent, and they are often associated with psychopathology in child and adolescent samples. For example, negative life events have been associated with antisocial behaviour (Wiesner and Windle 2004), depression (Kendler et al. 1999; Patton et al. 2003), and the overlap between them (Kim et al. 2003; Rowe et al. 2006). Parental negativity has been linked to anxiety disorders (Hudson and Rapee, 2001) and low self control in children (Cecil et al. 2012). As well as being phenotypically related to psychopathology, negative life events and parental negativity share genetic variance with commonly occurring behavioural and emotional problems: Genetic overlap has been reported between negative life events and depression (Kendler and Karkowski-Shuman 1997), anxiety (Boer et al. 2002), and antisocial behaviour (Button et al. 2008). Twin studies have also shown parental negativity to be genetically correlated with depression (Pike et al. 1996), and antisocial behaviour (Button et al. 2008; Narusyte et al. 2011; Pike et al. 1996).
