Gratitude predicts best friends' aggressive behaviors but not depressive symptoms: A dyadic study of Chinese early adolescents.

Gratitude has been empirically linked to psychological and behavioral adjustment outcomes during early adolescence. However, the role of gratitude in relation to friends' adjustment outcomes remains unclear, particularly in more interdependent-oriented cultures. To address this gap, this 1-year longitudinal study applied the Actor-Partner Interdependence Model to simultaneously examine whether gratitude would predict adolescents' and their best friends' depressive symptoms and aggressive behaviors. The sample consisted of 1342 students within 671 friendship dyads, initially in the fourth grade (44.0% boy-dyads; initial Mage = 10.22 years, SD = 0.33). The results indicated that adolescents' gratitude negatively predicted both their own and their best friends' subsequent aggressive behaviors, revealing both actor and partner effects. In addition, adolescents' gratitude only negatively predicted their own subsequent depressive symptoms. The aforementioned findings were stable across gender. The results suggest that adolescents with higher levels of gratitude can contribute positively not only to their own adjustment but also to the development of those around them. These findings deepen the understanding of the "firewall" function of gratitude and highlight the critical role of friendships in mitigating adolescents' maladjustment, offering practical implications for school-based gratitude education.