A small-scale exploratory study (Ginsberg, Ayers, Burriss, & Powell, 2004) was extended to include additional participants. Results of the two studies showed a high degree of agreement and, taken together, indicate that retrospective appraisal of low magnitude adverse experiences in childhood (before age 17) may be significantly associated with post-discharge traumatic stress (PTS) in combat veterans. The number of adverse childhood experiences per individual veteran was not found to be significantly associated with PTS or other psychological outcome (state anxiety, trait anxiety, or depression). However, ratings of fear of physical effects from childhood adversity were positively and significantly correlated with PTS, and of equal significance with combat exposure in explaining PTS variance. Increased ratings of fear of childhood adversity also were significantly associated with chronicity of PTS in all participants. These results support a conclusion that retrospectively assessed childhood reactivity may represent a marker of vulnerability to chronic PTS among veterans. Further research that overcomes methodological weaknesses, explores possible mechanisms of instatement of childhood reactivity, and elaborates the relationship between reactivity and stable personality traits is needed. Practice implications manifestly include assessment and prognostication of chronic traumatic stress reactions as well as sensitivity to and incorporation of early life issues into treatment approaches.