<p>Adolescents are highly sensitive to peer influence and thus at higher risk of acquiring problematic behaviors through peer interactions. However, adolescents vary in the extent to which they are influenced by their peers. Resistance to peer influence (RPI), the tendency to refuse undesired peer norms and peer pressure, is one of the crucial explanations for this variation. Prior to designing effective interventive plans to improve RPI, it is important to elucidate the pathways of how RPI develops in childhood and adolescence. Therefore, the present study leverages an adopted-at-birth design and proposes a moderated mediation model to examine whether: 1) child phenotypic impulsivity mediates the association between birth parent impulsivity and adolescent RPI; 2) child phenotypic self-esteem mediates the association between birth parent self-esteem and adolescent RPI; 3) adoptive parent responsiveness buffers the impulsivity pathway; and 4) adoptive parent responsiveness strengthens the self-esteem pathway. The sample consists of 538 family triads, with adopted child, birth parents, and adoptive parents, drawn from a sample of 561 families recruited from 45 adoption agencies in the United States. Birth parents’ impulsivity and self-esteem were measured to index heritable factors for phenotypic impulsivity and self-esteem. Adoptive parents’ responsiveness was measured via home observations. Impulsivity and self-esteem of adopted adolescent were reported by their adoptive parents, whereas RPI was assessed via self-report. Covariates included adolescent sex, age, and the openness to adoption between birth parents and adoptive parents. Results of structural equation models revealed that none of the proposed mediating or moderating pathways reached statistically significant levels. Overall, girls reported higher RPI than boys. For future studies, researchers may want to consider more accurate proxies of genetic factors for impulsivity and self-esteem, and repeated measures designs.</p>