Caregiving for children with neurodevelopmental disorders (NDDs) is a profound challenge shaped by local cultural and systemic contexts. In Vietnam, where parents contend with significant social stigma and systemic barriers, online platforms have become vital support hubs. However, the specific emotional and thematic landscape of these digital discussions remains under-quantified. This study leverages Natural Language Processing (NLP) to analyze public online discourse among Vietnamese caregivers. Our integrated sentiment and topic analysis reveals a striking prevalence of negative sentiment, driven by three core stressors: pervasive social stigma, severe financial burden, and systemic difficulties in accessing effective care. By quantitatively characterizing these challenges, this paper not only illuminates critical service gaps but also provides an empirical foundation for a proposed solution: a Culturally-Sensitive, AI-Powered Digital Support Platform designed to provide scalable, data-driven support.