--- - |2 Abstract Parenting interventions represent a means for experimentally inquiring socio‐emotional change of post‐institutionalized children after adoption. We used this approach in a three time point RCT study involving 83 post‐institutionalized children (Mage = 33.5 months, SD = 17.1) and their adoptive mothers (Mage = 42.6, SD = 3.9), attending either the Video‐Feedback Intervention to promote Positive Parenting in adoption and foster care or a dummy intervention. Controlling for gender and age at adoption, children showed a significant change in their socio‐emotional adjustment in the specific variables inquired—that is, emotional availability‐EA, and behavioral problems—after intervention attendance. Mediation and moderated mediation models showed that maternal EA was a main factor affecting children’s EA and externalizing behavioral problems, with a key moderating role played by children’s temperament; children with high scores on temperamental negative affect benefitted most from their mothers’ increase in EA. - Social Development, EarlyView.