"In terms of alcohol, some (19, 20) but not other (21) studies have linked parental alcohol and substance use to adolescent initiation of alcohol use. Several studies (14, 22) have identified disruption of family structure and social networks that use alcohol as a risk factor for initiation of alcohol use. Although there are few comparisons of the role of familial and social network determinants in the initiation of licit drug use, a cross-sectional study of 2,017 high school students found that social network characteristics were more important than familial characteristics in explaining cigarette and alcohol use (16).
"Thus, characteristics of one’s family during childhood and adolescence (including poor relationships between parents and children, parental educational attainment, and possibly parental substance use) appear to be the primary social factors associated with smoking and alcohol initiation. However, characteristics of families may be less important in specific groups where other social circumstances, including social network use of substances or recent migration, may be more important."
Galea, Sandro; Nandi, Arijit; and Vlahov, David, "The Social Epidemiology of Substance Use," Epidemiologic Reviews (Baltimore, MD: Johns Hopkins Bloomberg School of Public Health, 2004) Vol. 26, p. 39.