'Grey's Anatomy': Nia Vardalos and Peri Gilpin to Guest Star (Exclusive)

GettyNia Vardalos and Peri Gilpin A new pair of sisters will be joining Meredith and Lexie on Grey's Anatomy. My Big Fat Greek Weddingstar Nia Vardalos and Frasier's Peri Gilpin will guest star on an episode of the ABC medical drama, The Hollywood Reporter has learned exclusively. Vardalos, whose TV work includes stints on Cougar Town, Drop Dead Diva and My Boys, will play Karen Winterbottom, while Make It or Break It's Gilpin will play her sister, Marcy, on an episode of the Shonda Rhimes series. The bickering sisters will come to Seattle Grace during an episode slated to air in mid-January. STORY: ABC Studios Developing Star Vehicle for 'My Big Fat Greek Wedding' Actress Vardalos' casting comes nearly two weeks after Grey's and Cougar Town producer ABC Studios announced it was developing a comedy for the actress, who is married to Cougar Town's Ian Gomez. "Because Iangets treated really well onCougar Town,I wanted to get in on that action," Vardalos said at the time. STORY: 'Grey's Anatomy's' Kim Raver on Handling Tragedy: Teddy Will Be Different Than Izzie Gilpin, meanwhile, stars on ABC Family's Make It or Break It and played Roz Doyle for 11 seasons on NBC's Frasier. Vardalos is repped by Paradigm and Untitled Entertainment; Gilpin is with Innovative Artists, Burstein Company and Bloom Hergott. Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit RELATED: 'Grey's Anatomy's' Kevin McKidd: Owen and Cristina Have 'Brushed A Lot Under the Carpet' ABC Nia Vardalos Peri Gilpin Grey's Anatomy