Designing healthcare interventions for children with complex health needs often overlooks the perspectives of key stakeholders, including children. Collaborative design is essential for creating solutions that integrate diverse viewpoints and bridge communication gaps. However, prior studies lack tools to align stakeholder perspectives in pediatric care. This study introduces Octo, an educational toy, as a boundary object to enhance communication among children aged 4 to 10 with congenital heart disease (CHD), their parents, and healthcare providers. Octo evolves from a prototype to a functional educational tool, fostering engagement through play while promoting health literacy and stakeholder collaboration. This research through design (RtD) demonstrates the effectiveness of boundary objects in advancing inclusive, child-led interventions and collaborative healthcare design.
