Mirella Freni (Fregni) was Pavarotti's childhood friend from the town of Modena, Italy (where they make balsamic vinegar). She was training in opera and was the person who convinced Pavarotti to train to be an operatic tenor rather than a soccer goalie.
In this scene from La Boheme, both of them sing in a celebrated performance: http://www.youtube.com/watch?v=t0-1sQ0XOGE <http://www.youtube.com/watch?v=t0-1sQ0XOGE> <http://www.youtube.com/watch?v=t0-1sQ0XOGE>
