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As it turns out, she was also one of the first to hear Sheeran's song, "Thinking Out Loud," which won him the Grammy. In a heartfelt message posted on Instagram Wednesday, Swift, 26, gushed about her best friend's success while wishing him a happy 25th birthday.
"Looking back on the highlights of my life, there's a moment I'll never forget from a day in London about two years ago. I was in town to play the O2 and I was out shopping on my day off. My friend Ed Sheeran met up with me in this little shop where I was buying ballet shoes. He walks in and says 'you have to hear this new song. I think it's the best one I've ever written.' And then, as usual, he pulls out his phone and gives me headphones," Swift captioned a photo of Sheeran collecting his Grammy.
"I sat there on a bench in that store and heard 'Thinking Out Loud' for the first time, as little kids were picking out tutus and leotards next to us," she continued. "Little did we know it would go on to be first dance song at countless weddings all over the world, become Ed's biggest hit, and eventually go on to win him Song of the Year at the 2016 Grammys."
Swift, who won three Grammys herself Monday night, including album of the year, then recalled the year she spent on tour with Sheeran, who was her opening act.
"Ed and I had been on tour together all year on the Red Tour and we saw each other almost every day," she wrote. "I lived for the moments he would burst into my dressing room with a new song to play me. It happened so often that it became normal, and I don't think he ever knew how much it meant to me that he wanted me to hear his songs first."
She added: "I don't think he ever knew how inspired I was by his drive and passion to constantly create new art. But it's his 25th birthday today, so I'm saying it now. You deserve everything you have, and everything you will continue to achieve, Ed."