Pete Shotton, known in Beatles lore as John Lennon's best friend during their childhood days in Liverpool and a member of Quarrymen, has passed away. He was 75.

The Liverpool Echo reported the news, saying that it's believed that he had a heart attack. Carl Cookson, a neighbor of his, remembered him as "a very modest and unassuming man -- a really warm and nice person.”

“Pete was the closest friend John ever had, apart from the Beatles," Bill Harry, the publisher of Mersey Beat, the Liverpool newspaper that played a large role in the group's early days, told the Echo. "John respected Pete because he stood up to him and could be a bit like John – a bit sarcastic and moody. John went to Pete for advice on lots of things, and their friendship from schooldays continued right through the 1960s. And I know they did meet up in New York in the 1970s.”

Shotton met Lennon when they were six and pupils at Dovedale Primary School. The two were so close that they were known around school as “Shennon and Lotton” or “Lotton and Shennon.” In 1956, Lennon decided to form a skiffle group called the Quarrymen, so named after Quarry Bank High School, and Shotton joined on percussion, playing a washboard. He left a year later, shortly after Lennon met Paul McCartney, because they were moving more towards rock, thus negating the for a washboard.

He had a certain stature inside the Beatles' camp. “One thing he was really proud of was that he was at times the only person, outside the Beatles and the producer, engineer and technicians, who was allowed in the studio with the band when they were recording,” his step-son, Phillip Goldbourn, said, adding, “He remained close to John until Yoko Ono came on the scene. He said she took him from being a pop star to an artist and he respected that and took a back seat.”

It's believed that Shotton was involved in two of the Beatles' most beloved songs. The line “Yellow matter custard / Dripping from a dead dog’s eye” in "I Am the Walrus" reportedly came about when Lennon asked Shotton about a schoolyard nursery rhyme that they used to sing, which Shotton remembered as “Yellow matter custard, green slop pie / All mixed together with a dead dog’s eye."

On "In My Life," the lyric "Some are dead and some are living" is rumored to be a reference to former Beatles bassist Stu Sutcliffe, who died in 1962, and Shotton.

With Lennon's financial help, Shotton bought a supermarket on Hayling Island, off the South Coast of England. In 1983, he founded Fatty Arbuckle's, a chain of American-style diners, which he owned until the early '00s.

In 1983, Shotton wrote John Lennon: In My Life, which was later re-titled The Beatles, Lennon and Me.

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