Language and self-regulation develop bidirectionally, and they synergistically affect most aspects of acquiring reading proficiency. Children and youth from historically marginalized communities tend to have less expansive knowledge of academic vocabulary and dialect common to instruction and academic text (i.e., General American English), and limited self-regulation skills relevant to reading, compared to less-marginalized peers. In this article, we argue that language and self-regulation are factors in demographic-related reading opportunity gaps, and that in addition to improving students' access to high-quality explicit phonics instruction, understanding their interactive relationship offers opportunities for schools to reduce disparities in reading outcomes.