Production has begun in Los Angeles on the fourth series of 'Grey's Anatomy'.
The new series sees the main characters begin their first year as residents at Seattle Grace Hospital with their own interns to mentor.
Among the new interns is Lexie Grey (Chyler Leigh), Meredith's (Ellen Pompeo) half-sister.
In other related 'Grey's Anatomy' news, actress KaDee Strickland is joining the cast of the spin-off series 'Private Practice'.
It focuses on Dr Addison Forbes Montgomery (Kate Walsh); Strickland will play Charlotte, a doctor and hospital administrator.
