Organizations have adopted social media to communicate their alliances to the public, that is, engage in representational networks. Yet a comprehensive examination of what is communicated in representational networks and how public reactions are associated with these networks is relatively scarce. This study builds on the Symbiotic Sustainability Model (SSM) to examine the content of messages passed in representational networks on social media and their related public reactions. Based on a panel analysis of one year of Facebook data generated by 605 public organizations in Taiwan, this study reveals that referencing certain topics such as economic and technological development and employing linguistic features demonstrating efficacy, formality, and empathetic concern in Facebook messages was associated with an increased diversity of alliance ties reported by public organizations. Moreover, the relationship between communicating diverse alliance ties and positive public reactions in the form of likes went both ways. Integrating automated topic modeling, linguistic analysis, and panel analysis, this study provides a process-based and communication-centered view of the mechanisms and disparities underlying organizations’ strategic network management on social media.