Willa Holland played the character Thea Queen who is Oliver Queen’s sister in Arrow. Just as Oliver Queen backed his sister Thea’s decision to put Star City in the rearview mirror, Arrow‘s main lead Stephen Amell supports Willa Holland’s decision to exit the series after the better part of 131 episodes.
As showrunner Marc Guggenheim shared, Holland had been arguing to leave Arrow since season 4. As she was under contract the producers decided to reduce the number of episodes she was gonna air in. Finally, in the 16th episode of season 6 of Arrow, Thea left town with longtime love Roy Harper and former League of Assassins honcho Nyssa al Ghul, to destroy a trio of hidden Lazarus Pits. These pits were discovered by her late father Malcolm Merlyn. They had to get to them before they fell into the wrong hands.
After that, we knew that she was not going to return to Arrow but she again made an appearance in the 150th Episode of Arrow titled “Emerald Archer” which was kind of a documentary episode for Oliver Queen. There are however speculations that Willa Holland is gonna return for the finale of Arrow season 7 or for the cross-over in Season 8 titled “Crisis on Infinite Earths”.There are rumors that Oliver Queen is most likely to die.