As every parent knows, children tend to pick up more of what they observe than what they are told, and parents don\u2019t get to choose which habits children will imitate. A new study reveals that parents who abuse substances are more likely to have children who do the same. The study from Sam Houston State University is not groundbreaking in the sense that no one has known the power of parent modeling before, but it is among the first to show at what point substance use behaviors begin to be copied and how parent behavior impacts the substance use decisions in offspring. The study, which covered 1977-2004, followed three generations to look at family substance use. The long-term view revealed not only when children started to repeat the substance use modeled by parents, but it also provided insight into when that use begins to decline. Researchers tracked 655 parents and 1,227 children through the 27 years of study. Data was collected through the National Youth Survey Family Study. Review of the survey data showed that when parents use alcohol their children have a five times greater likelihood of also using alcohol, children whose mother or father used marijuana were two times more likely to smoke pot and children with parents who used other drugs were also twice as likely to use illicit drugs compared to children of drug-free parents. Researchers found that use of marijuana and other illicit drugs most often started during adolescence and then started tapering off by age 24. Children of alcohol consuming parents also tended to start drinking in adolescence, but their drinking seemed to climb steadily from adolescence into early adulthood at which point it seemed to level off. Whether or not kids are at risk for alcohol and drug use is an important public concern. Kids who use drugs demonstrate lower school achievement, lower employment, have more health issues, are more apt to become socially dependent and are more often involved with crime as either a victim or as a perpetrator. Alcohol and drug use cost Americans roughly $600 billion each year, mostly through higher healthcare costs and lowered productivity at work. According to the 2011 National Survey on Drug Use and Health it\u2019s a problem affecting millions of Americans. That survey found that 22.6 million Americans age 12 or older reported using illicit substances within the last 30 days. The Sam Houston study suggests that a lot of the behavior was first learned at home.