<P> Benjamin Lindsay, Backstage 2015 </P> <P> On April 5, 2014, TVLine reported that Kelly McCreary best known for her series regular role on The CW's short lived medical drama Emily Owens, M.D. and recent guest appearances on Scandal had been cast in a guest star role . McCeary was slated to debut on the May 8, 2015 episode . On October 23, 2014, it was announced that McCreary was promoted to series regular after being credited as guest - starring until the eleventh episode . It was a couple of months after McCreary wrapped her stint on Scandal that she was invited to audition for Grey's . McCeary revealed that she originally auditioned for the character of "Claudette" with dummy sides, unbeknownst to her . The only information McCeary had about the character was "that she was adopted, that she would recur, and she was going to be a very important storyline ." Just before the script reading for the season 10 finale, Rhimes summoned McCeary to inform her of Maggie's true identity . "I was really psyched" McCeary revealed when Rhimes informed her of Maggie's lineage . "I felt really honored to be the one to accept the challenge ." However, it wasn't until McCeary experienced the reactions to Maggie's existence from her fellow cast mates that McCeary realized just how big of a deal the character would be . </P> <P> The character's potential existence was first referenced in the press in February 2009 when Michael Ausiello hinted at the possibility of Meredith having a half - sibling, the product of her mother's affair with Richard . Initial speculation pointed to Jesse Williams' Jackson Avery as the child, but the actor refuted those rumors . Shonda Rhimes revealed that the character had always been a part of the original story plans, but the character's existence was not set in stone until season 4 . </P> <P> Kelly McCeary expressed her excitement about how special Maggie in an interview with BuddyTV . "I just feel like it's a rare opportunity to be able to play somebody that is so complex and fully realized and smart and fierce and compassionate and awkward and the whole thing ." Maggie is very good at her job so she can find a place in a professional capacity, but in her personal life, she "gets more than she bargained for" McCreary said . "I think she's a really good doctor" McCeary said of Maggie . "She's obviously super-bright . She's very young to be as high in her field as she is ." McCeary further described Maggie as a "really great problem - solver ." Maggie is "very compassionate" and at the same time can "keep a clear head and do the right thing medically all the time ." McCeary further described Maggie as "so dynamic ." While Maggie initially "came across as all business," Kelly McCeary relishes in playing "Maggie's neurotic, existential, meltdown side ." "Maggie also won't really back down from a fight; she's very decisive ." </P>

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