Research demonstrates students with a family member serving in the military often experience deleterious effects on their developmental outcomes. This study addresses two knowledge gaps in this area of research. First, we present a conceptualization of a unique typology of military connectedness, including the potentially unique effect of having both an adult and sibling in the military. Second, the analysis used sophisticated propensity score techniques to properly control for substantive and methodological differences arising from hidden selection bias. Multinomial propensity score matching was used to analyze a large, diverse sample of middle- and high school students (N = 9,536; mean age: 13 years). Results show statistically significant differences exist between adult-only, sibling-only, and adult + sibling military connections. Implications include the need for research to statistically model adult + sibling military connections, and for practitioners to consider how various forms of military connectedness might differentially influence children's development.