Children’s relationships with their siblings and friends serve as important contexts for interaction and development, particularly with respect to their conflictual exchanges (Piaget, 1965; Sullivan, 1953; Volling, 2003). In particular, the various forms of power children use in conflict are suggested to play a significant role in their socialization process (Hartup, 1989; Hinde, 1979; Dunn, 2002) Further, it has been argued that a science of relationships should be studied through the interplay of both relationship and actor-partner effects (Hinde, Finkenauer, & Auhagen, 2001). To this end, the present two studies examined children’s individual and dyadic use of power in sibling and friend conflict across the early and middle childhood period. Specifically, the first manuscript comprising a cross-sectional examination focused on siblings’ and friends’ dyadic use of power resources and effectiveness in conflict during early childhood, whereas the second manuscript performed a longitudinal investigation of focal children’s use of power resources and effectiveness in conflict with their siblings and friends across the early and middle childhood period. Data based upon naturalistic observations of semi-structured play sessions were previously collected (DeHart, 1999). Behavioural coding of the transcripts was used to quantify conflict sequence identification and power behaviours (i.e., resources and effectiveness). Results are discussed in light of previous theoretical and empirical research concerning the developmental significance of children’s agency (i.e., power) in conflict with an accompanying focus on future research recommendations. Overall, the results showed patterns of interaction that highlight the construct of power as
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an ability that may or may not always be exercised and even when exercised may be more or less effective depending on level of analysis, relationship partner, developmental stage, and conflict process or outcome.