Paul McCartney recalled writing Beatles songs with John Lennon in his bedroom. At the time, Paul didn’t analyze the meaning of one of The Beatles’ songs. Subsequently, Paul wondered if John may have written the song about his mother.In the 1997 book Paul McCartney: Many Years From Now, Paul said he and John used to spend time together in John’s bedroom. They used to listen to Chuck Berry, Fats Domino, and Jerry Lee Lewis songs together. Paul said these memories make him nostalgic.“It’s a lovely thought to think of a friend’s bedroom then,” Paul said. “A young boy’s bedroom is such a comfortable place, like my son’s bedroom is now; he’s got all his stuff that he needs: a candle, guitar, a book.”
Source: cheatsheet.com