“The Descendants” thesp Mary Birdsong, “Community” star Yvette Nicole Brown and Missi Pyle have been cast as the three Fates in Fox 2000′s “Percy Jackson & The Olympians: Sea of Monsters.”Thor Fredenthal is directing the pic from a script by Scott Alexander and Larry Karaszewski. Chris Columbus, who directed the first film, will produce with Karen Rosenfelt and Michael Barnathan. Sequel, which is skedded for release on March 27, 2013, finds Jackson and his friends heading to the Sea of Monsters to find the mythical Golden Fleece. Logan Lerman is returning as the title character, while Alexandra Daddario, Brandon T. Jackson, Jake Abel and Melina Kanakaredes will also reprise their roles from the first pic, which grossed $226.5 million worldwide back in 2010. The three Fates will be portrayed as taxi-driving sisters who bicker over the single eye they share.”Big Love” thesp Douglas Smith is also a newcomer to the franchise, playing the protag’s half-brother, a Cyclops. Birdsong, who recently played Zach Galifianakis’ ex-girlfriend in Focus’ “It’s Kind of a Funny Story,” next stars in Brian O’Connell’s indie comedy “Angry White Man.” Thesp is repped by UTA and Abrams Entertainment.