Thea is Oliver's younger sister.

Thea Queen Quotes

Oliver: This guy gets more airtime on the Kardashians.
Thea: Five years on an island and you still know who they are.

Thea: I missed you so much.
Oliver: You were with me the whole time.

Arrow Quotes

Ra's al Ghul: You tasted death and you wanted more, but the truth is everyone and everything must come to an end. Even for one such as me.
Oliver: Kill me, but spare John Diggle's life. Let him go. I will beg for it.
Ra's al Ghul: You have shown tremendous strength, fortitude, power. No, Mr. Queen. I don't want to kill you. I want you to take my place. I want you to become the next Ra's al Ghul.

You know Oliver, somebody once told me that secrets have weight. The more you keep, the harder it is to keep moving.

Diggle