Understanding How Parental Caregiving Influences the Child’s Attachment in Adoptive and Biological Relationships

Background: Despite decades of attachment research, the "transmission gap" persists in understanding how parental caregiving influences child attachment, with parental sensitivity explaining only 25-50% of variance in parent-child attachment relationships. This gap is particularly pronounced in adoptive families where children's pre-adoption trauma intersects with new caregiving relationships. Aims: This study examined attachment and caregiving processes in adoptive and biological families, understanding how past experiences and present caregiving interact to shape parent-child attachment relationships. Methods: A systematic literature review synthesised evidence from 32 studies examining factors influencing child attachment in adoptive families. The empirical study employed an idiographic theory building multiple case study design with eight parent-child dyads (five adoptive, three biological) with children aged 5-8 years. Three standardised attachment procedures were used: the Berkeley 6-year-old reunion procedure, the Meaning of the Child Interview (MotC), and the Child Attachment and Play Assessment (CAPA). Data were analysed through within-case and between-case analysis using both the Berkeley (ABC+D) and the Dynamic Maturational Model (DMM) frameworks. Results: The systematic review revealed complex, interacting factors influencing attachment beyond parental sensitivity, including pre-adoption experiences, contextual factors, and bidirectional parent-child processes. The empirical study found that adoptive children showed more complex attachment strategies than biological families, of which adoptive children with organised attachment strategies may paradoxically be more resistant to change compared to children with unresolved trauma who showed potential for attachment reorganisation. "Insecure" strategies often appeared contextually adaptive rather than pathological. Both adoptive and biological families predominantly showed defensive attachment strategies to different extent, suggesting adaptation to specific relational contexts rather than global security or insecurity. Conclusions: This research contributes to understanding the transmission gap by demonstrating that attachment and caregiving function through systemic cycles involving dynamic interplay between historical experiences, current challenges, and ongoing meaning-making processes. The study offers theoretical contributions that emphasise the importance of a contextual understanding of defensive strategies within their protective functions rather than viewing them as deficits. Clinical implications include the need for contextual, non-pathologising interventions that honour families' adaptive strategies while supporting exploration of potentially more fulfilling relational possibilities.