Longitudinal child cohort studies collect large amounts of information about children’s families and the types of activities they participate in. With such a broad array of information to select from, researchers investigating aspects of the family environment may be overwhelmed by the choices available if they only need summary measures reflecting domains of the family environment. Using data from the Longitudinal Study of Australian Children, this study aimed to derive and assess summary indices of three domains of the family environment, including a Family Stress Index, Home Education Index and Parenting Index. Indices were derived by identifying a set of candidate indicators, dichotomising the indicators to determine elements of risk, then averaging across the dichotomised items to create measures that captured cumulative risk. Assessments of the three indices suggest that the measures are consistent across time, and have good predictive validity with socioeconomic measures and assessments of children’s social-emotional wellbeing and learning outcomes. Structural equation models estimating children’s outcomes suggested that models using the indices had comparable model fit to models using the broader array of variables used to construct the indices, but the Parenting Index in particular explained less variation in children’s problem behaviour outcomes. Overall, the family environment indices derived in this study may be useful for researchers wishing to simplify complex models or explore the circumstances of children exposed to multiple risks, but less useful in analyses where the primary goal is to explain variance in children’s developmental outcomes.