Starting out early in the acting world clearly runs in Emma Watson's family. The 17-year-old Harry Potter star, who made her big screen debut as the teenage wizard's loyal friend Hermione Granger six years ago is now to be followed into the profession by her little sisters. But while Emma's first major role, aged 11, was impressive enough, she has been topped by her sisters, who have landed their first jobs at the tender age of three.The girls, Nina and Lucy - identical twins from the second marriage of Emma's father - are to join their famous sibling in a BBC production of Ballet Shoes. An adaptation of the novel by British author Noel Streatfield, it's due to be screened on BBC1 in December.In the 1930s drama, Emma's first major role away from Hogwarts, she plays orphan Pauline Fossil, a young girl who, along with her two adopted sisters, begins attending a stage and dance school while their eccentric father is away hunting for fossils. Emma's sisters meanwhile will take it in turns to appear as a two-year-old Pauline.