"...The "Lucy" who inspired this song was Lucy O'Donnell (later Lucy Vodden), who was a classmate of John's son Julian Lennon when he was enrolled at the private Heath House School, in Weybridge, Surrey. It was in a 1975 interview that Lennon said "Julian came in one day with a picture about a school friend of his named Lucy. He had sketched in some stars in the sky and called it Lucy In The Sky With Diamonds."..."

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