This case study explores the role of adult siblings in bridging and brokering cultural and linguistic gaps in special education on behalf of their sibling with a disability. Focusing on the Le family, the study explores how Eunice Le, an adult sibling, is navigating communication between their Vietnamese-speaking family and the school, and advocating for their brother Kai, a culturally and linguistically diverse (CLD) student with autism. The case is premised on two key provisions within the Individuals with Disabilities Education Act (IDEA) that center on the Individualized Education Program (IEP) team configuration and parent participation. This case reveals the difficulties that arise when schools and families have divergent approaches to supporting students with disabilities and their extended families from racialized and minoritized communities.