Oliver's two biggest sidekicks on the show - Felicity and Diggle - are new creations, although he's had some of his comic-book friends come along as well, such as Black Canary and Roy as Arsenal. In the comics, Roy also goes by the name of Speedy, and that's a name later picked up by Mia Dearden. She's not in the show, but the Speedy title has, as revealed at the end of season 3, been taken on by Oliver's sister, Thea. Again she's a show character, but the parallels to Mia are obvious - they look a bit alike, their first names rhyme, and Thea's middle name is Dearden. She's going to be the show's version of Mia, and thus it seems her and Olly will be spending a lot more time together. Roy was quite an angsty sidekick, which went well with the tone of the show last year, but now it'd be good to have a proper take on the bright, quip-happy Speedy.