Conor's father says that he will get a legal separation, but cannot divorce his wife. This is true for the time the film is set in (1985). Divorce only became possible in Ireland in 1997.
Mark McKenna plays Eamon: a young talented Irish guy with a musician father. In real life Mark McKenna's father is a musician named Eamon.
Two of the songs on the soundtrack, "Go Now" and "Don't Go Down", are written by Glen Hansard, the Dublin native artist who won an Oscar for his song "Falling Slowly", featured on "Once", another John Carney movie.
In the scene where Conor and Raphina have a conversation in the orphanage for the first time, heard in the background is a slow piano version of a-ha's "Take on Me", the first song Conor sings to her.