The current study explored dynamics of secure state attachment expectations in everyday life in middle childhood, specifically state attachment carry-over and reactivity to experiences of caregiver support in the context of stress. In two independent samples (one community sample, N = 123; one adoption sample, N = 69), children (8–12 years) daily reported on their state attachment for respectively 14 and 7 consecutive days. Additionally, they reported daily on their experiences of distress and subsequent experiences of caregiver support. Results in both samples indicated that secure state attachment on a day-to-day basis is characterized by a significant positive carry-over effect, suggesting that state attachment fluctuations are (partially) self-predictive. In Study 1, experiencing no support following distress significantly related to intraindividual decreases in secure state attachment; in Study 2, experiencing effective support during distress related to intra-individual increases in secure state attachment. Taken together, the current studies provide novel and important insights into how state attachment temporally evolves on a day-to-day basis in middle childhood.

Secure attachment is characterised by a secure base script regarding the attachment figure as a source for support. Having such a cognitive script should affect the stability of state attachment. Specifically, incongruent attachment-related information should get assimilated to this secure base script, leading to state attachment scores that hardly fluctuate. For children without a script, state attachment should vary depending on the quality of attachment-related interactions. Two diary studies were carried out in 9- to 13-year-old children. Results suggested that with assimilation: (1) securely attached children fluctuated less in their daily attachment-related appraisals; (2) fluctuations were related to conflicts with mother; (3) this relation was stronger for less securely attached children. Consequently, these studies further support the secure base script hypothesis and provide insight into the interplay of trait and state components of attachment-related appraisals.