The present study investigated child depression symptoms, social skills, and mother-child conflict from mid-childhood to mid-adolescence. Bidirectional effects involving all three constructs were anticipated, as were differential effects for child gender. Participants included 893 families from the Study of Early Child Care and Youth Development (SECCYD). Data were from assessments at three developmental time points: grade 5, grade 6, and age 15 years (grade 9). Analyses involved the application of a cross-lagged panel model (CLPM) and a random intercept cross-lagged panel model (RI-CLPM), the latter of which decomposes state- and trait-level variance. The RI-CLPM yielded superior model fit and fewer significant state-level (situational) associations. Stronger trait-level effects were observed for boys and stronger state-level effects for girls, although no cross-lagged associations were significant. Results align with a growing body of research revealing low or no situational dependence between child social skills development, emotional adjustment, and family relationship quality.