Objective: Transgenerational trauma (TT) occurs when trauma exposed parents transfer the effects of trauma to their descendants. While empirical evidence informs that TT exists, clarity is needed to distinguish TT from other specific traumas and to better understand how trauma responses transfer to future generations. TT research tends to focus on particular groups (e.g., Holocaust survivors and their offspring). Considering contextual factors associated with TT is important; but shared aspects of TT across groups may also occur. Comprehensively identifying and quantifying TT would aid in effectively developing and assessing programs to mitigate adverse effects of TT exposure. Thus, this research aimed to develop and evaluate the Family Impact Scale (FIS), a measure being developed to assess TT. Method: This mixed methods online study included 301 participants ages 18 to 25. Respondents represented a community (82%) and college (18%) sample and completed three measures, the FIS, the Posttraumatic Stress Checklist for DSM-5 (PCL-5), and a sociodemographic questionnaire. Qualitative and quantitative methods were used for data analysis. Results: Factor analysis of the 26 quantitative FIS items revealed five factors: dangerous place, overprotection, role reversal, perception of parental inadequacy, and perception of impact on participant. Factor and qualitative data analyses supported the removal of three items. Two items related to the importance of exposure to things outside of one’s community, and one item aimed to capture using parental behavior to determine what to and not to do. Omega coefficients and a polychoric correlation (one factor had two items) suggest good internal reliability for all factors, except dangerous place. The dangerous place factor may be acceptable, given this research’s exploratory nature, but is uncertain. The perception of parental inadequacy and perception of impact on participant factors were moderately related to PCL-5 scores. Conclusion: In this study, the FIS items supported a five factor model, adding insight regarding factors related to TT. Moreover, the factors less prominently discussed in the reviewed literature, perception of parental inadequacy and perception of impact on participant factors, showed an association with symptoms of traumatic stress. Thus, this research evidences promise for further FIS development.