This study maps early adulthood family life courses from ages 15 to 28 and tests whether they are causally linked to neighbourhood conditions with an instrumental strategy in the United States using Add Health data. Results show that the risk of sorting into pathways typified by early childbearing regardless of relationship status was higher in disadvantaged neighbourhoods. The instrumental variable strategy further showed that pathways characterized by single parenthood and early marriage with multiple children increased significantly with neighbourhood disadvantage, whereas other significant associations disappeared in these analyses. Overall, the results highlight the importance of considering multiple family events as a process outcome to understand the impact of neighbourhood conditions. Indeed, neighbourhood deprivation may lead to life courses associated with nonconventional outcomes. While some of the observed neighbourhood effects may be driven by selection bias in the United States, not all effects are necessarily due to selection and depend on the longitudinal family trajectories. These results were supported by several robustness tests, including the use of an alternative instrumental variable, as the main models suggested weak identification.