Preview for the upcoming "Grey's Anatomy" episode shows that a young woman is convinced she is the long-lost daughter of McSteamy. Just in time for holiday, Mark is given a possible family member when a patient requires a surgery and recognizes him. Lexie consequently has to cope with the shocking arrival from her lover's past.
The episode is called "Holidaze" and will air on November 19. As Thanksgiving, Christmas and New Year's pass, Miranda is visited by her father, William, who disapproves of her choices in life. Thatcher Grey questions the Chief's recent behavior as Meredith comes to his defense.
Leven Rambin, known as Riley on "Terminator: The Sarah Connor Chronicles", is guest starring as the young woman confessing as Mark's daughter. The character reportedly will also be part of the crossover to "Private Practice" since she needs the help from Addison in Los Angeles.