Although individuals are exposed to a variety of pro-environmental influences in childhood, it is unclear which has the biggest impact on adult beliefs and behaviour. The aim of the current study therefore examined how formal sustainability education and childhood caregiver pro-environmental motivations, beliefs and behaviour, influence motivations and behaviours in adulthood. An Australian adult sample (n = 230) completed a survey measuring pro-environmental motivation, anthropogenic climate change beliefs and pro-environmental behaviour. Recollections of childhood caregivers’ anthropogenic climate change beliefs and pro-environmental behaviours, and formal completion of sustainability education were obtained. Hierarchical multiple regression analysis found childhood caregiver pro-environmental behaviour significantly and uniquely predicted pro-environmental behaviour. Moderation analysis found no influence from formal sustainability education on this relationship. Caregiver and individual climate change belief were associated, but caregiver belief was not associated with pro-environmental motivation. No differences in adult pro-environmental behaviour were noted when considering childhood sustainability education. Results suggest transmission of anthropogenic climate change belief and pro-environmental behaviour occurs from childhood caregivers. Comparatively, formal childhood sustainability education was not significant in establishing ongoing pro-environmental behaviour patterns. This research adds to limited existing literature demonstrating caregiver impact on sustained pro-environmental behaviour and provides possible future direction for promoting sustainable behaviour.