Willa Joanna Chance Holland (born June 18, 1991) is an American actress and fashion model. She is best known for her role as Thea Queen, Oliver Queen's rebellious younger sister, on the television series Arrow. She also appeared as Agnes Andrews on The CW series Gossip Girl, as well as The O.C. Since 2010's Birth By Sleep, she has provided the voice of Aqua in the Kingdom Hearts video game franchise.