The influence of parents' smoking was found to be substantial during adolescence for all smoking transitions (from never smoking to trying, trying to monthly, monthly to daily smoking) and increased significantly for the transition from monthly to daily smoking as the adolescent grew older. In contrast, the influence of close friends' smoking was strongest for the transition to trying smoking and did not significantly change for any of the smoking transitions as the adolescent became older.
J.B. Bricker, A.V. Peterson, I.G. Sarason, M.R. Andersen, and K.B. Rajan. Changes in the influence of parents' and close friends' smoking on adolescent smoking transitions. Addictive Behaviors, Vol. 32, Issue 4, pages 740-757, April 2007. Abstract
Having one parent who smokes doubles the risk that children will be daily smokers by 12th grade.
A.V. Peterson, B.G. Leroux, J.B. Bricker, K.A. Kealey, P.M. Marek, I.G. Sarason, and M.R. Andersen. Nine-year prediction of adolescent smoking by number of smoking parents. Addictive Behaviors, Vol. 31, Issue 5, pages 788-801, May 2006. Abstract
Parents who quit smoking when their children are young reduce the risk by more than a third that their children will be daily smokers at 12th grade.
J.B. Bricker, B.G. Leroux, A.V. Peterson, K.A. Kealey, I.G. Sarason, M.R. Andersen, and P.M. Marek. Nine-year prospective relationship between parental smoking cessation and children's daily smoking. Addiction, Vol. 98, Issue 5, pages 585-593, May 2003. Abstract
Children with one or more older siblings who smoke are 1-1/2 times more likely to smoke than children with nonsmoking siblings.
K.B. Rajan, B.G. Leroux, A.V. Peterson, J.B. Bricker, M.R. Andersen, K.A. Kealey, and I.G. Sarason. Nine-year prospective association between older siblings' smoking and children's daily smoking. Journal of Adolescent Health, Vol. 33, Issue 1, pages 25-30, July 2003. Abstract