Social-Emotional-Learning (SEL) is an empirically grounded and lifelong developmental issue, beginning in early childhood environments and influencing students' mental health, academic achievement, and interpersonal relationships. Empirical research shows that parents' emotions, behaviors, and parenting practices exert profound effects on young children's social and emotional competence. Theoretical perspectives further suggest that children's social-emotional development is closely tied to the growth of their language abilities. Therefore, the present study investigates how parental behaviors—including caregiving, discipline, nurturing, companionship, and educational practices—cultivate children's language competence and social-emotional development.
Based on the Taiwan Kindergarten Panel Study (KIT) dataset (N = 1,668, male= 832), this study analyzed a four-year longitudinal sample of children aged 3 to 6 using latent growth modeling. Using the dataset's item sets, the study verified good reliability and validity, while controlling for family income and gender. Results showed that both paternal and maternal parenting behaviors significantly predicted children's language competence (father: β = .125, p < .001; mother: β = .169, p < .001). In turn, language competence strongly predicted emotional competence (β = .604, p < .001) and social competence (β = .588, p < .001). Importantly, indirect effects confirmed that parental behaviors influenced both emotional (father: β = .081, p < .001; mother: β = .102, p < .001) and social competence (father: β = .073, p < .001; mother: β = .100, p < .001) through children's language ability. However, small negative effects were found on developmental slopes (e.g., father to emotional slope β = -.019, p < .001; mother to social slope β = -.019, p < .001), suggesting ceiling effects in measurement or complex developmental dynamics. Two explanations are considered: (1) the measurement instruments leaded a ceiling effect; and (2)Important theoretical and methodological implications that warrant further clarification and refined research designs in future.