MLS follows over 2,200 individuals from 460 families, tracking the life trajectories of children, particularly those of parents who are alcoholic, compared to children from non-alcoholic families. It aims to investigate the relationship between behaviour, social dynamics, brain vulnerability, and genetic predispositions in shaping substance abuse risk and resilience across the lifespan and across generations. The study also has a focus on archiving observational data initially captured on VHS tapes and now in MP4 format.