We are constantly learning about new characters on Pretty Little Liars, but on the 6B finale, we possibly learned about one of the most important ones. Toby, Spencer, and Mona (yes, Mona) found the birth records for Charles Drake, which revealed that Charlotte was adopted into the DiLaurentis family. So, who is Mary Drake on Pretty Little Liars? Well, she's just be the secret twin we've all been waiting to discover.
On the Pretty Little Liars 6B finale, Spencer, Toby, and Mona discovered the very old, very cleverly placed birth records for Charlotte (born Charles Drake). The three learned that Charlotte was adopted by the DiLaurentis family and that Charlotte was just about the same age as Jason was. Plot twist. Mary Drake was marked down as Charles Drake's birth mother.
It all begins to make sense when the pieces of the very messy puzzle fall into place — Mary Drake is Jessica DiLaurentis' twin sister. We learn this when Elliot and and Mary are in Ali's house, basically vowing to continue the terror that Charlotte once placed on the Liars. Mary says that she and Elliot can "finally take back" what was supposed to be theirs... is that threatening enough for you? Because it is for me.
So, we know Mary Drake is Charlotte's birth mom, but could she possibly be Elliot's birth mom, too? I can't think of any other reason these two would be working together. Plus, Elliot told Ali — in the finale — that he would have done anything for Charlotte. Hey, foreshadowing, I see you.
I don't know what these two have planned for the Liars, but I can tell you it isn't going to be pretty. It seems like they're starting with Hanna, who is maybe dead, maybe not. I just hope that the Mary Drake clue is enough for the Liars to figure out whatever the hell is going on, because if not, Season 7 is going to be brutal for them.