<![CDATA[Language acquisition during early childhood is closely associated with cognitive development and shaped through meaningful social interaction. However, empirical evidence explaining how cognitive development influences language acquisition in authentic Indonesian kindergarten classrooms remains limited. This study explored the relationship between cognitive development and language acquisition among Indonesian early childhood learners through naturally occurring classroom interactions. A qualitative multiple-case study involved 30 children aged 4–6 years from four kindergartens in Sukoharjo Regency, Central Java, Indonesia. Conducted from January to March 2026, data were collected through classroom observations, semi-structured teacher interviews, and document analysis and analyzed using the interactive model of Miles, Huberman, and Saldaña, supported by triangulation and member checking. The findings revealed two major themes. First, children's spontaneous utterances accompanied by gestures, including pointing, object manipulation, smiling, and eye contact, reflected symbolic thinking, conceptual understanding, categorization, and meaning construction during language production. Second, teachers' verbal and non-verbal responses, including open-ended questions, positive reinforcement, repetition, clarification, eye contact, and demonstrative gestures, served as effective scaffolding supporting cognitive development and language acquisition. The findings indicate that language acquisition is a dynamic process emerging from reciprocal interactions between children's cognitive construction and teachers' instructional support. This study contributes empirical evidence from Indonesian early childhood education and supports an integrated perspective combining Piaget's cognitive constructivism, Vygotsky's sociocultural theory, and Bruner's interactionist approach, while offering practical implications for developing cognitively stimulating and interaction-rich language learning environments in early childhood education.]]>
