It’s surprising how cheerful it can be at the Children’s Hospital of Philadelphia, but in the battle against pediatric cancer, smiles are as important as drugs and surgery.

That’s the reason why Hoda Kotb, herself a breast cancer survivor, felt it was important to bring some joy to the children being treated there. She launched “Project Truly Brave”: a musical collaboration between Sara Bareilles and Cyndi Lauper starring a beautiful and brave group of kids fighting cancer.