Top row: Tristan and Gabriel Harland, left, Ruari Spooner. Bottom row: Gracie Cochrane, left, Alastair Stout. (HBO)The Weasley family is growing! More Weasley children have been cast for the upcoming Harry Potter TV series that will air in 2027, HBO announced Tuesday.Mischievous twin brothers Fred and George will be played by Tristan and Gabriel Harland, respectively, while Ruari Spooner has been cast as elder brother Percy, and Gracie Cochrane has been cast as younger sister Ginny.James and Oliver Phelps originated the role of the twins in the Warner Bros.