Recent outbreaks of measles have centered in specific communities, pointing to the influence of social ties on vaccination practices. This study adds to the conversation on public understanding of vaccine-related science, documenting how the individualist epistemologies highlighted in prior research are externalized and validated in communication with others, focusing on how the narrative strategies used to do so contribute to community building among vaccine refusing and hesitant parents. Through qualitative content analysis of testimonials given to the creators of the anti-vaccination documentary VaxXed, we identify how the common narrative strategies used to question the scientific consensus on vaccines—distrust of doctors, self-diagnosis, building credibility, advocacy, and community building—build a competing consensus based on personal expertise. With this approach, we are better able to understand how participation in online communities strengthens the privileging of individualist epistemologies among vaccine refusing and hesitant parents.