A seven-year longitudinal study was conducted as part of the French national cohort ELFE (N = 1095). The aim was to identify how and why early language skills at 2 years might predict later literacy skills assessed successively at 5, 7, and 9 years (LitSk5y; 7y; 9y). Using one and the same model, we also examined the relations between literacy skills in the three sessions and the potential impact of three environmental variables: the home learning environment (HLE) and two variables related to socioeconomic status (SES), namely parental education level (PEL) and household income (HInc). The main findings reveal that expressive vocabulary at 2 years is a significant predictor of LitSk5y. No significant link was found for HLE. The other significant links reveal that PEL is associated with LitSk5y and LitSk7y, and HInc with LitSk5y and LitSk9y. The differential impact of these two SES variables is discussed. Moreover, the Restructuring Lexical Model is proposed to explain how the development of early expressive vocabulary is linked to the development of literacy skills via an implicit stimulation of phonemic awareness during the acquisition of new words.