This study aimed to investigate the roles of transcription skills and oral language abilities in predicting writing quality and productivity among Spanish-speaking kindergarten children (N = 159). Using Structural Equation Modeling (SEM), the study examined associations between these foundational skills and writing outcomes. The model demonstrated excellent fit, with significant relationships between observed measures and their respective latent variables. Transcription skills were found to robustly predict both writing quality and productivity, while oral language was a significant predictor only for writing quality. A notable covariance was observed between transcription and oral language constructs, emphasizing their interconnected influence on early writing development. The study’s findings contribute to the current discourse by aligning with the ‘not-so-simple’ view of writing, challenging conventional notions that prioritize transcription skills over oral language in early writing. These results have important implications for designing comprehensive early childhood literacy programs and suggest that both transcription and oral language abilities should be integrated for holistic writing development. Limitations and directions for future research are also discussed.