mona is hannas best friend and shes a in the book
Alison picked on Mona when they were younger.
Monda knows secrets about the girls in Pretty Little Liars from cameras and rumors.
no Mona only knows that the girls have something to hide so she will find out soon in the new season of Pretty Little Liars in January
she found Ali's (Courtney's) diary
She happens to know most their secrets because of Jenna.
-A-.... She is stalking them and now, we know that one of -A-'s helpers is Mona
She has Ali's old diary from when she died and knows all of their secrets!
She knew it was her when she saw the gum wrapper and when she saw the cashmere sweaters.
Because Spencer put together all the clues that Mona had accidentaly given to the girls.
because ali a never liked her and know that she mean to Hannah she want to give revenge
She might not dies we don't know that but the is in a mental hospital right now and Hannah ( Ashley Benson ) and the rest of the liars is trying to find out if Mona is a BTW Mona was set up to look like she was A but in the book series Mona is A.
Mona in the first 4 books, Alison in the last 4.Dying to know who I am? You'll find out.- A