Wikipedia
Falsettoland
Falsettoland is a musical with a book by James Lapine and music and lyrics by William Finn.
Following In Trousers and March of the Falsettos, it is the third in a trio of one-act musicals centering on Marvin, his wife Trina, his psychiatrist Mendel, his son Jason, and his gay lover Whizzer Brown. In this chapter of Marvin's life, Jason is preparing for his bar mitzvah and Whizzer is suffering from a mysterious, life-threatening, as yet undefined illness, which the audience recognizes is AIDS.