Although prior research has independently linked vocabulary development with toddlers media usage, parental mental state talk (MST), and parent-child conversational turn-taking (CTT), these variables have not been investigated within the same study. In this study, we focus on associations between these variables and 2-year-olds (N = 87) vocabulary. Child vocabulary and digital media use were measured through online questionnaires. We took a multimethod approach to measure parents child-directed talk. First, we used a home sound environment recording (Language ENvironment Analysis technology) to estimate parents talk (CTT). Second, parents narrated a picture book, the Frog story, to assess the parents MST. There was a negative association between how much children watched video content and their vocabulary. However, parents reported that they frequently co-viewed and engaged with the child and media. The negative association first displayed between the amount of video content viewed and the childs developing vocabulary was fully mediated by the parents qualitative and quantitative talk as measured by MST and CCT, respectively. We propose that the parent relative level of MST and CTT also occurs when parents engage with the child during media use.