The development of children’s language skills during the preschool years plays a crucial role in subsequent reading and school success. Some children may enter kindergarten with oral language skills that lag behind their peers’. Two such groups are children from low-socioeconomic status (SES) families and those who are deaf or hard of hearing (DHH). Study 1 considered parents’ linguistic input during interactions with their Head Start pre-kindergarten children in two conversational contexts. The first, shared storybook reading, has featured prominently in early language interventions but proven less efficacious among low-SES samples. The second, shared reminiscing, offers a theoretically promising setting in which to promote child vocabulary skills but lacks empirical support. This study examined features of parental language known to relate to children’s vocabulary, including parents’ quantity of speech, lexical diversity, syntactic complexity, and intent to elicit child language. Parents’ and children’s expressive vocabulary knowledge was also considered. Forty parent-child dyads’ conversations during storybook reading and shared reminiscing were audiorecorded, transcribed, analyzed, and coded. Paired t-tests revealed that, while parents talked more during book reading, they used greater levels of syntactic complexity and language-eliciting talk during shared reminiscing. Parents’ own vocabulary knowledge was related to their children’s but not to linguistic input in either context. Study 2 considered the oral narrative skills of DHH preschoolers relative to language-matched hearing children. School-age DHH children often experience delays in the development of narrative skills compared to their hearing peers. Little is known about the narrative abilities of DHH children during the preschool years. This study examined 46 DHH and 58 vocabulary-matched hearing preschoolers’ overall language production, lexical diversity, syntactic complexity, and narrative comprehension skills. DHH children produced a similar number of words and demonstrated similar levels of narrative understanding compared to their hearing peers. However, DHH children’s narratives contained significantly less complex syntax. Gains in lexical diversity differed by group, with DHH children demonstrating less growth over the course of the school year despite making more gains on a standardized measure of vocabulary. Implications for instruction, assessment, and future research are discussed for both low-SES and DHH children.