Earlier puberty predicts emotional symptoms during adolescence, with potential sex disparities in how developmental contexts moderate this relationship. Under the differential susceptibility framework, negative contextual amplifiers are well-documented, but positive contextual attenuators remain under-researched. Acknowledging girls' earlier pubertal onset, this study employed a dual grade cohort design (5th- and 7th-grade cohorts) to examine sex-specific positive contextual moderators (family members, general peers, teachers) in the longitudinal association between pubertal timing and emotional symptoms. This approach enabled sex comparisons at similar chronological ages (controlling for social timing) and at comparable pubertal stages (accounting for measurement timing). Multiple grade cohorts from a three-wave survey in China were analyzed, including six-month (5th: N = 10,544, 46.6% girls; 6th: N = 5991, 47.6% girls; 7th: N = 7028, 47.4% girls; 8th: N = 4832, 48.2% girls) and one-year (5th: N = 14,580, 45.8% girls; 6th: N = 11,845, 46.6% girls; 7th: N = 10,347, 47.6% girls) nested samples. Through within-grade and cross-grade comparisons, linear mixed-effects models tested each pubertal timing x positive context x sex interaction in predicting future emotional symptoms, adjusting for school-level clustering, socio-demographics, and baseline emotional symptoms. Results identified earlier puberty as a risk for both sexes. Results revealed schoolwide teacher-student relations as a positive contextual moderator only for 5th-grade girls, with no other significant contextual moderators observed for either sex. These findings underscore the importance of improving school-level teacher-student interactions to mitigate the emotional challenges faced by early-maturing girls.
