Background: Since the life expectancy of people with profound intellectual and multiple disabilities (PIMD) is increasing, siblings may take over care/support roles from their parents. Method: To explore how parents and siblings of persons with PIMD view siblings' role regarding future care/support for their family member, we interviewed eight parents and 13 siblings of seven persons with PIMD and analysed the data thematically. Results: While some parents expected that a future care/support role would burden the sibling unfairly, most siblings anticipated such a role and reported no concerns about this future responsibility. Despite a lack of explicit communication, expectations of parents and siblings regarding future responsibilities corresponded. However, some siblings mentioned the lack of explicit communication made them feel unprepared for the future. Conclusions: Explicit family communication may make siblings feel more prepared for the future and decrease the discrepancy between parents' and siblings' views regarding an expected future burden.