Which Beatle made Elton John the godfather of his son?

John Lennon made Elton John the godfather of his son, Sean Lennon.

Sean was born on October 9, 1975, to John Lennon and Yoko Ono. Elton John and Lennon were close friends and musical collaborators during the 1970s, making Elton a natural choice for the ceremonial role. Elton later described the relationship warmly and remained connected to the Lennon family.

The friendship grew partly through music. Lennon played guitar on Elton John's 1974 recording of “Whatever Gets You Thru the Night,” which became Lennon's first solo number-one single in the United States. Elton also performed on the track and helped persuade Lennon to play live with him at Madison Square Garden in November 1974; it was Lennon's final major concert appearance.

The question can cause confusion because Sean Lennon was born to John Lennon, while Julian Lennon was John's older son from his marriage to Cynthia Powell. Elton John is Sean's godfather, not Julian's. Sean later became a musician himself, following both his father's and his mother's artistic paths.