Initially, Prince refused to allow the use of his song, "Kiss", for the film. However, after seeing footage of the film, he not only changed his mind and allowed the song to be used, but also wrote an additional original song for the film to use in the closing credits.
"The Song of the Heart" is the final original song that Prince created for a movie. The song won him his only Golden Globe Award and he received a Grammy nomination for it as well.
Norma Jean and Memphis are obviously named for Marilyn Monroe (who was born Norma Jean Mortensen) and Elvis Presley (who lived in Memphis, Tennessee). Their voices and mannerisms are imitations.