The 13-year-old had no idea that when she signed up to perform at her local fundraiser concert for the Edmonton Humane Society in Edmonton, Canada that it would make worldwide headlines.
In the viral video, an unsuspecting Sydney performs on stage as Ed sneaks into the shopping centre.
“I’m just going to sing with someone,” the 24-year-old popstar beams at the camera, before adding: “should I just roll up?”
Didn’t expect to see you here! 13-year-old Sydney got the shock of her life when Ed rocked up.
The British crooner proceeds to creep onto the stage behind Sydney before greeting her with a friendly hug.
In a scene straight out of a film clip, Ed and Sydney then perform a touching duet as the crowd cheer in delight.
It’s not the first time the Give Me Love hitmaker has surprised a fan – in March the red-headed rockstar delivered an moving performance of the same single for a Sydney couple’s first dance.
This is one dedicated man to his fans! And just when you thought you couldn’t love him anymore!
Watch the heart-warming clip in the player above
Hitting all the right notes: The pair relieved an impromptu duet of Ed’s hit Thinking Out Loud
