Saul Austerlitz's new book Generation Friends, timed with the NBC sitcom's 25th anniversary on Sept. 22 with a Sept. 17 release date, offers some of the known and unknown casting stories, including Jennifer Aniston's conflict with another sitcom and Janeane Garofalo being offered the role of a harder-edged Monica. The producers, he writes in an EW book excerpt, also "expressed a desire to be open about race and ethnicity as well. They knew that the Ross and Monica characters were to be siblings, and had decided that they would be played by white performers, but were open to anyone for the other four roles. (Casting director Ellie) Kanner’s initial lists included numerous African-American and Asian-American performers. The flexibility was a step forward, to be sure, but some of Friends‘ later struggles regarding diversity were etched in stone here. Without an explicit desire to cast actors who looked more like New York, the producers were likely going to end up, as if by default, with an all-white cast."