Watch Ed Sheeran sing to Bruno Mars in strange birthday celebration

"You know you’ve made it when you can hire Ed Sheeran to sing you Happy Birthday!"

This is what Bruno Mars captioned this video of Ed Sheeran singing him Happy Birthday.

Fans have taken to Twitter to question how much Bruno paid Ed to do this, while others have claimed that it was out of the kindness of his heart. 

Right now we don't know what actually happened, but it's a good watch none the less.