Why Some Children Are Kind and Others Act Out. It Is Not…

Why Some Children Are Kind and Others Act Out. It Is Not Genetics. It Is Environment. The relationship between prosocial behaviour and conduct problems in children has been studied for decades. The consistent finding is that they are negatively correlated: children who help, share, and comfort others tend to show fewer disruptive behaviours, and vice versa. What has remained unclear is why. Is this relationship driven by shared genes? By the same family environment shaping both traits simultaneously? Or by some other mechanism? A twin study published in Personality and Individual Differences using 1,198 South Korean children provides the clearest answer yet and the finding has direct relevance for paediatric practice and child mental health. Researchers drew from the South Korean Twin Registry, comparing 485 monozygotic and 713 dizygotic twin pairs between ages 4 and 12. Mothers rated children on the prosocial behaviour and conduct problems scales of the Strengths and Difficulties Questionnaire: a validated tool widely used in paediatric and child psychiatric settings. The phenotypic correlation between prosocial behaviour and conduct problems was −0.34. Children scoring higher on prosocial behaviour consistently scored lower on conduct problems, and the relationship was robust across the sample. The key question was what drives this correlation. Using bivariate model-fitting ana