Support exchange between siblings in later life: the role of "core-kinlessness" and geographic proximity.

Suicide is one of the leading causes of death among young adults, defined in our study as individuals aged 18–29, worldwide (World Health Organization ). While STBs occur across the lifespan, they often first onset during adolescence (Voss et al. ), and the rate of suicide deaths increases significantly between early adolescence and young adulthood (Cha et al. ; Nock et al. ). Importantly, far more young adults experience SI than plan or attempt suicide (O'Connor et al. ). Thus, studies that catalog and examine the thoughts and behaviors that occur in response to SI can enhance our understanding of how some young adults transition from ideation to attempt. Nonetheless, there have been few efforts to operationalize and measure responses to SI. Coping with SI adaptively is crucial because doing so may prevent its future occurrence or may reduce the severity and consequences if SI reoccurs (Bryan et al. ). Indeed, in many first‐line interventions, individuals presenting with acute SI are assisted in identifying coping strategies for navigating future suicide crises (e.g., Stanley and Brown ; Tyndal et al. ). However, young adults with a history of SI express low‐to‐moderate confidence in their ability to apply coping strategies during crises (Czyz et al. ) and are reluctant to access professional or medical resources in such times (De Luca et al. ; Michelmore and Hindley ). The unique challenges of adolescence and young adulthood may partly explain the increased rate of SI in this developmental period, and associated difficulties in managing these cognitions. In late adolescence and early adulthood, individuals navigate changing social roles and more intimate relationships, while being tasked with forming a clearer sense of identity and pursuing higher education and/or employment (Shanahan ). These demands, along with age‐related changes in preference for and access to different coping strategies (e.g., greater preference for avoidance to manage sadness in young adulthood, Amirkhan and Auyeung ; Zimmermann and Iwanski ; increased access to alcohol and other substances; DiBello et al. ), may partially drive how young adults respond to SI, both over time and across contexts; however, the literature on these processes is in its infancy.