Background: Mothering children born unexpectedly with developmental disability has historically been shown to have a profound negative impact on maternal functioning. However, this study, which was designed to capture the lived experience of mothers whose children were diagnosed postnatally with Down syndrome, demonstrated the universal presence of factors of posttraumatic growth for all participants. Method: Mothers participated in 1 in-depth semistructured interview (N = 18). Feminist theory and thematic narrative analysis framed the data analysis. Results: Participants in this study universally reported 3 positive outcomes: development of formal/informal advocacy roles, improved mothering skills, and positive personal growth demonstrating the presence of all 5 domains of Calhoun and Tedeschi's posttraumatic growth model. Conclusions: This study highlights the potential for positive personal maternal growth for mothers unexpectedly raising children with Down syndrome, which can lead to individual personal and spiritual development, which in turn can have a powerful positive impact on the community as a whole.