In 1968, The Beatles faced challenges after the passing of their manager, Brian Epstein, but found solace and inspiration during a meditation retreat in Rishikesh, India. While there, John Lennon wrote the sweet ballad "Dear Prudence" for Mia Farrow's sister, Prudence, who was dedicated to learning meditation. The song was influenced by Lennon's time at the retreat and his friendship with Donovan, who taught him guitar techniques. Prudence Farrow, touched by the song's affectionate message, found it to be a flattering tribute to their time together. "Dear Prudence" remains a fan favorite for its simple yet moving lyrics and peaceful melody, showcasing The Beatles' enduring creativity and connection to their experiences in India.
Source: https://collider.com/john-lennon-classic-beatles-song-mia-farrow-sister-dear-prudence