"He ain't heavy, he's my brother": Distress tolerance moderates the association between secondary posttraumatic symptoms and secondary posttraumatic growth among siblings of combat veterans

Objective: Positive psychological and behavioral transformations in the form of posttraumatic growth (PTG) after indirect exposure to a traumatized family member, have been reported mainly among combat veterans' spouses and offspring (secondary posttraumatic growth; SPTG). To date, no studies have examined SPTG among veterans' siblings, and the conditions in which secondary posttraumatic symptoms (secondary PTSS) may contribute to the development of SPTG remain unexplored. In the present study, we aimed to explore the association between secondary PTSS and SPTG among siblings of combat veterans and to examine the moderating role of distress tolerance in this association. Method: A volunteers' sample of 106 dyads of Israeli combat veterans and their close-in-age siblings responded to online validated self-report questionnaires in a cross-sectional study. Analysis included actor-partner interdependence modeling (APIM) and moderation analyses. Results: Veterans' PTG was positively correlated with siblings' SPTG. Moreover, two actor effects were revealed wherein veterans' PTSS contributed to their own PTG, and siblings' secondary PTSS positively predicted their own SPTG. Importantly, analysis of moderation revealed that under high levels of secondary PTSS, the more siblings reported distress tolerance, the higher their own levels of SPTG. Conclusion: Exposure to a traumatized veteran brother or sister might entail psychological distress but also positive changes among siblings. The ability to withstand the emotional valence of negative or stressful events might hold a promise for the facilitation of higher levels of SPTG in the face of secondary PTSS.