Background Communicative and motor development is frequently found to be associated. In the current study we investigate to what extent communication and motor skills at 1½ years predict skills in the same domains at 3 years of age. Methods This study is based on the Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Heath. Data stem from 62 944 children and their mothers. Mothers completed questionnaires on their child's communication and motor skills at ages 1½ and 3. Associations between communication and motor skills were estimated in a cross‐lagged model with latent variables. Results Early communication skills were correlated with early motor skills (0.72). Stability was high (0.81) across time points for motor skills and somewhat lower (0.40) for communication skills. Early motor skills predicted later communication skills (0.38) whereas early communication skills negatively predicted later motor skills (−0.14). Conclusion Our findings provide support for the hypothesis that these two difficulties are not symptoms of separate disorders, but might rather be different manifestations of a common underlying neurodevelopmental weakness. However, there also seem to be specific developmental pathways for each domain. Besides theoretical interest, more knowledge about the relationship between these early skills might shed light upon early intervention strategies and preventive efforts commonly used with children with problems in these areas. Our findings suggest that the relationship between language and motor skills is not likely to be simple and directional but rather to be complex and multifaceted.