We don't know yet
Actually no...
she found Ali's (Courtney's) diary
Yes she is guilty for killing Courtney
Mona found Courtney's diary after she died. That's how she knew all the secrets.
Atually it's Courtney who is dead and her body was found in a hole in her backyard
If you are referring to Courtney from the Pretty Little Liars book series by Sara Shepard, it is unknown if it will be on the series. What I do happen to know is that we will find out who "-A" is at the end of Season 2. I found this out on the website, abcfamily.com and go to the Pretty Little Liars blog. As you know, Courtney was in the books, and honestly I hope she's on tv. That would be a great twist. Hope this helps a little, considering it's the best to anyone's knowledge at the moment.
melrose rabbotinini killed her sister Courtney they found ali under a treeNot exactly....
Ali came back and found out that Courtney was pretending to be her the whole time. So Ali took her and buried her alive for revenge.
Yes. She was the one that was friends with the girls so she wrote down what they told her
I can't exactly remember which book it was they found out, but one day Ali's parents released to the press that Ali had a twin sister named Courtney. I believe they did this outside their house, and the Pretty Little Liars were listening in the crowd.
Well, honestly when I found out that Alison wasn't really Alison and was her twin Courtney who was pretending to be her and had befriended Aria, Emily, Spencer, and Hanna
Mona was trying to freak the girls out at first but when Ali found out Ali turned into A because Ali is not dead her twin sister Courtney is.