Infants’ Negative Emotionality and Regulatory Behavior: A Moderated Moderation Model of Maternal Interactional-Effectiveness and Parenting Sense of Competence

Objective: This study examined the moderated moderation effects of maternal interactional-effectiveness (MIE) and parenting sense of competence (PSC) in the relationship between infants’ negative emotionality and regulatory behavior. Given that infants with difficult temperaments are more strongly shaped by their caregiving environment, this study investigated how MIE and PSC jointly serve as protective factors, and whether the interplay between these two maternal resources differs according to mothers’ level of competence.Methods: Participants were 356 mothers of children in the first and second stages of the Korean Early Childhood Education & Care Panel Study. Data were analyzed using SPSS 25.0, and PROCESS macro model 3.Results: First, negative emotionality alone did not significantly predict regulatory behavior. Second, the threeway interaction effect was significant. Conditional slopes revealed that at low PSC, high MIE served as a protective factor for highly negative-emotional infants’ regulatory behavior, whereas at mean PSC, this MIE benefit was reduced. This pattern suggests that MIE functions as a compensatory resource, exerting its greatest protective influence precisely when mothers’ PSC is low. At high PSC, the moderating effect of MIE was no longer significant.Conclusion: These results highlight the importance of interaction-focused interventions, particularly for mothers with low PSC raising temperamentally difficult infants. This finding suggests that even when mothers raising temperamentally difficult infants report low PSC, the provision of sensitive