when does lexie come in grey's anatomy
Lexie Grey Leigh first appeared on the show during the last two episodes of the third season as Meredith's half-sister, Lexie Grey. Following Isaiah Washington's departure who portrayed Preston Burke, it was reported that show's executives were planning on adding new cast members, such as Lexie.[6] She was officially upgraded to a series' regular on July 11, 2007, for the fourth season.[7] On casting Chyler Leigh as Lexie, Grey's Anatomy creator Shonda Rhimes said: "We met with a lot of young actresses, but Chyler stood outâ€”she had a quality that felt right and real to me. It felt like she could be Meredith's sister, but she had a depth that was very interesting."[8]