The findings of this study point to a central insight: the adult dynamics that emerge when a step-family is formed play a crucial role in shaping how stepchildren adjust to the new family structure. These dynamics played out across four key relational domains, each capturing a different layer of adult involvement and interaction, from parenting decisions to the wider social messages stepchildren receive. Across these domains, we observed how alignment or tension among adults could either support or hinder stepchildren’s adaptability to step-family life.

A key insight is the pervasive ambiguity around roles within step-families, especially concerning the position and responsibilities of step-parents. This ambiguity often leaves children uncertain and unsupported, illustrating a gap in communication and role negotiation that, if addressed, could significantly ease family tensions and foster clearer expectations.

Moreover, we find that cooperative co-parenting across households, although relatively uncommon in our sample, can improve stepchildren’s experiences. This underscores the potential impact of strengthening inter-adult collaboration beyond the immediate household. Studies have shown that children in step-families fared better when co-parents worked collaboratively (Ganong et al., 2022). Importantly, as other scholars have noted (e.g., Ahrons, 2007; Ganong, Sanner et al., 2021), effective co-parenting does not require the absence of conflict, but rather the minimisation of children’s direct exposure and emotional entanglement in adult disputes.

Crucially, our study highlights that adult dynamics — particularly how conflict is managed and how cooperation is modelled — form the emotional architecture within which stepchildren make sense of their family transitions.

Extended family members also emerged as important influencers, either reinforcing children’s sense of belonging or deepening feelings of exclusion. The variable involvement of extended kin points to the need for inclusive strategies that recognise the broader family network’s role in children’s adjustment.

These findings also point to the role of institutions, such as schools, in mediating step-family experiences. While not always visible in daily family life, these institutions often serve as the only external environment where stepchildren’s needs might be noticed and addressed. While some supportive encounters were noted, many participants reported a lack of support and understanding in schools.

Taken together, these findings call for intentional support systems that equip both adults and institutions such as schools to better navigate and nurture these relationships, ultimately enhancing the support available to stepchildren.