Ed Sheeran's 'We Are' was inspired by the tragic death of a close friend.
Although the track has not been included on any of Ed's three number one albums, he added it to his set at The Bedford pub in Balham in 2010, which he recorded for a self-released live EP.
Ed calls the track "the song that actually got me a record deal" as a record executive from Atlantic was in the audience and was hugely impressed by the emotional song.
Ed, 27, was just 14 when his close pal Stuart Dines died in a traffic accident near Cologne in 2006, while on a school ski-trip.
He was so devastated by his loss that he wrote 'We Are' and Stuart's family played it at his funeral.
In his book 'Ed Sheeran', author Sean Smith explained: "Ed had to come to terms with the death of someone he saw practically every day.
"He resolved to write a song about his feelings. He composed it, he said, 'whilst I got round to actually accepting it'."
And Stuart's dad Robert told the author: "Ed was very, very upset, like a lot of the children."
In an extract from the book, which has been obtained by the Sunday Mirror, Sean also revealed that Ed's first serious girlfriend Alice broke up with him because she was uncomfortable with being the inspiration behind many of his songs.
A source told the author: "She was incredibly self-conscious about the fact the album was very heavily about her.
"Her boyfriend was the Ed Sheeran she went to school with and now it was something completely different. She wanted no part of fame. She cared greatly about him. They were wonderful together."
However, Ed still paid tribute to her in the notes for his first album, writing: "Finally thank you to Alice, all in, chill out time, and being the only girl that all of the songs are about, thank you for the inspiration and for staying you. Love x (sic)."
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