As one of the most common mental health disorders in the world, depression represents a major concern for those who have the condition and their close relational partners. Extant literature has prioritized depression in romantic and parent-child relationships. The sibling bond is underexamined, despite the uniqueness of the relationship and siblings’ positive role in mental health. Family systems theory frames the family as a complex system of interdependent individuals and relationships (or subsystems). Because system-level patterns are transmitted intergenerationally, family systems theory argues that depression is not solely a contributor to negative family outcomes, but also the result of maladaptive system patterns developed over the family’s history. Family communication research has traditionally centered on a given dyad or triad in a singular interaction or set of interactions. This neglects the influence of other family members, interacting subsystems, and previous experiences. That is, the sibling’s navigation of depression is not merely a dyadic issue, as the sibling subsystem is situated within the larger family system. Therefore, the present study seeks to describe the family system-related dilemmas faced by emerging adults who take on the supporting sibling (SS) role for their sibling with depression (SWD).

Inconsistent nurturing as control (INC) theory posits that close relational partners of individuals who display undesirable behavior have conflicting goals to nurture and control. Consequently, unafflicted partners respond to afflicted partners’ undesirable behavior in inconsistent ways that unintentionally reinforce the behavior. Although INC theory was originally created to describe the maintenance of problematic substance use in romantic couples, it has been applied to a variety of health disorders and family relationships. Sibling depression represents an intersection unexamined through an INC lens. As such, the present study investigates SSs’ communicative management of their family system-related dilemmas pertaining to their SWD’s condition, with the objectives of better understanding the SS’s experience and gauging the applicability of INC theory to siblings and depression.

Fifty emerging adults who grew up with at least one sibling, and one or both of the siblings having chronic depression, participated in individual semi-structured interviews about sibling management of depression in the family system. A thematic analysis revealed several interrelated themes demonstrating the relevance of the larger family system in all parts of the navigation of sibling depression. Insufficient support from older generations, combined with care for their SWD, contributed to emerging adults’ felt obligation to upholding the SS role. They grappled with internal tension as they struggled to balance their family relationships, SWD’s needs, and their own well-being and autonomy. Findings are elaborated upon, and implications for family systems research, INC theory, and practice are discussed.