In season 3, episode 13, Thea finally learns that her brother, Oliver Queen is the Arrow.
But I thought that Thea already found out who the Arrow is at the end of season 2. At one of the end episodes of season 2, Thea learns the secret of both her mother and her brother. This triggers her disappointment in her family members and she decides to get away with her biological father, Malcom Merilyn for quite a while.
Any reason Thea suffers amnesia? Or is it that this is just one of the plot holes of the TV series?
Note: I am just half way through season 3, so please don't spoil the remaining season!