Teachers' ratings of conflict and closeness as well as observed emotional support are known predictors of children's social functioning. Consistency in emotional support represents an emerging line of research. The goal of the present study is to understand whether the relation between the consistency of teachers' emotional support and children's behavior is mediated by teacher-child relationships. The role of gender is also considered. Using MPlus, the present study examines the indirect effect of emotional support consistency in prekindergarten on children's social competence and problem behaviors. Outcomes are extended to kindergarten to test the lasting association between the prekindergarten social environment and child behavior in the kindergarten year. Multigroup models examine gender differences. Research Findings: Observations of 694 prekindergarten classrooms revealed that teachers' emotional support consistency had an indirect effect on social competence and problem behavior through conflict in the teacher-child relationship in prekindergarten and kindergarten. The indirect effect on prekindergarten problem behaviors through conflict was stronger for boys. For closeness, all outcomes were significant with the exception of the indirect effect on problem behaviors in the kindergarten year. Practice or Policy: Consistency in prekindergarten teachers' emotional support has an indirect effect on children's behavior in prekindergarten and the following year in kindergarten through teacher-child relationships. Improving teachers' emotional support consistency may be one avenue for strengthening teacher-child relationships.