A recent study using the same sample of adolescent children suggested that parental knowledge was associated with substance initiation in young adulthood via two distinct mechanisms: one, a shared environmental influence common to decreased parental knowledge and deviant peer affiliation during mid-adolescence and substance initiation by early adulthood, and the other a common genetic liability such that adolescents’ genetic influences contributed to the same three factors (Neiderhiser, Marceau, & Reiss, 2013). This finding suggests that multiple mechanisms may simultaneously influence how parents gain knowledge of their adolescents’ whereabouts and activities, and the effectiveness of parental knowledge. Here, the association between parental knowledge and reduced externalizing was not large, so we may not have had sufficient statistical power (see below) to uncover both a direct environmental influence from parents to adolescents and a smaller evocative effect from adolescents to parents as the literature suggests (e.g., Laird et al., 2003; Pardini et al., 2008; Willoughby & Hamza, 2011).
