Children who grow up in families who are affiliated with violent extremism and terrorism are frequently viewed through a security-oriented lens which focuses on their risk of radicalisation, or the security risk they may pose to society. This security-oriented approach limits a broader understanding of the multiple ways in which a child’s life may be impacted when an immediate family member is involved in terrorism. To rectify this, this paper highlights the utility of Bronfenbrenner’s Ecological Systems Theory (EST) to systematically identify how this familial affiliation may impact the child’s life in diverse ways that extend beyond security-oriented outcomes. We demonstrate that EST is particularly useful because it allows us to systematically and holistically understand how the life of the child is impacted by familial association with a terrorist group in multiple spheres of their life (family, education, peer groups, etc.). We apply this approach to an example of a family who travelled to Syria in 2015 to join ISIS. This article demonstrates the utility of EST for researchers and practitioners to better understand the impact of familial involvement in terrorist groups on children moving away from more security-oriented approaches.