Military families navigate a combination of normative and military-specific stressors, and thereby may be at greater risk for experiencing interparental conflict (IPC). Using the ABCX Model, IPC was conceptualized as a family stressor associated with adolescent siblings’ distress outcomes (i.e., greater anxiety, lower positive adjustment), and siblings’ appraisals of IPC were conceptualized as the linking mechanism in this relationship. Within 117 military families, a service member parent, a civilian parent, and two siblings each individually reported on IPC in their family and the siblings reported on their own distress. Civilian parents’ reports of IPC were positively associated with their children’s IPC appraisals, but service member parents’ reports were not associated with their children’s IPC appraisals. Siblings who appraised greater IPC showed higher anxiety and lower positive adjustment outcomes. The indirect link between parent IPC reports and sibling outcomes, via sibling IPC appraisals, was significant for civilian but not service member parents across all outcomes. These findings highlight the importance of accounting for the health of the larger family system when working with adolescents and assessing the potential disconnect between parental accounts of IPC and adolescent appraisals of conflict when working with these families.