In this paper I examine the role of emotions in the initial development of self-awareness through intersubjective communication between mother and infant. I argue that the empirical evidence suggests that the infant's ability to communicate is initially an ability of the infant to share emotions with the mother. In section one I examine the biological foundations that allow infants from birth to interact with others of their own kind, focusing on the abilities which allow them to engage in emotional relationships with others. These include an infant's ability to express, share, and regulate emotions as well as her brain's ability to imitate the neuronal activity of another. In section two, I explore the fit between Sartre's phenomenologically-based account of intersubjectivity in Being and Nothingness and the accounts from psychology and neuroscience that I've examined in section one, focusing on his phenomenology of the Look and the emotional response he claims it elicits. In section three I examine the explanatory gap objection that Sartre among others could raise to my attempt to understand phenomenological accounts of human reality and scientific ones in light of each other. I don't have any final answer to this objection, but I offer some thoughts on why I think it's less of a problem than it might first appear to be.