Big-hearted fans from both clubs will collect money for the charity as they travel through to Hampden on Saturday.
The aim is to demonstrate how rival supporters can band together to do something positive for the city.
First Minister Alex Salmond said: “The Sick Kids is close to many people’s hearts. I’m sure that fans on the Hearts and Hibs supporters buses will dig deep.”
Maureen Harrison, chief executive of the Sick Kids Friends Foundation, said: “Saturday will be a big day for Edinburgh and the funds which are raised will make other days good for children at the hospital and their families.
“We wish to thank the Evening News for coming up with this fantastic idea.”