The whole letter Gerry sent to his Mom & Dad in Ireland says: "Dear Mum & Dad. Well, Doc says there's not much time so I thought I'd write to you, seeing how bad we Kennedy's are with modern day contraptions like telephones. Tell Dad to not lay about and to take care of his legs-keep them walking. I always think of Dad walking across the farm yelling after the hands too lazy to keep the chickens fed. And you Mum, yelling at Dad to treat the boys with a Father's hand, not a father's belt. I remember everything Mum. And I thank you for giving me a mother's breath of life and love. No son ever loved a mother more, I can tell you that. Never could say it to your face. Nor to Dad. But I love you."
According to the Christmas 2006 issue of People magazine, Jeffrey Dean Morgan had to learn to play the guitar for his part in this film in a very short time. His guitar instructor was Nancy Wilson of the band Heart. Morgan was thrilled to take lessons from her because, in his own words, "I had such a crush on her as a kid."
During the performance of "The Galway Girl" by William (Jeffrey Dean Morgan), Holly (Hilary Swank) flashes back to a performance of the same song by her late husband, Gerry (Gerard Butler). It is later discovered that William and Gerry were best friends, and William is seen briefly on stage with the rest of Gerry's band, during the flashback performance, while Gerry is singing to Holly.