Since 2013, the Roger Federer Foundation has been financing overnight stays at the Children's Hospital in Zurich for parents who cannot afford it. In 2018, 18 families with scarce financial resources received support from the Roger Federer Foundation so that parents could to stay for several weeks in a parental or family room and be close to their children.

A new KISPI building is opening in 2022. It is particularly important to the architects to make the building suitable for children and patients. The new building should give the children numerous opportunities to spend time in play areas and rooms. The Roger Federer Foundation has granted an amount of CHF 900,000 for the design of the play and learning facilities.

The KISPI and the playrooms are a matter which lie close to Mirka Federer’s heart. She is a member of the Board of Trustees of the Roger Federer Foundation. She is very committed to this project and brings new ideas and suggestions to make the hospital a happy place for children.