Tonight's Pretty Little Liars, "Original G'A'ngsters," dropped a major bombshell about the DiLaurentis/Drake family that could mean huge things when it comes to uncovering the identity of A. While investigating the late Jessica DiLaurentis' weird stalker bomb shelter, which was wallpapered with pictures of the Liars and Alison, the girls discovered something huge: Mary Drake had a second child after Charlotte. That child could be A.D., the unknown person stalking the girls and trying to discover Charlotte's killer. But who is Mary Drake's second child?
There are a few clues to go off of, but not many. The records the girls found didn't specify a name or gender, only that the birth was easy because Mary already had one child before. There was also a birth year that indicated the kid would now be the same age as the Liars themselves. That makes it seem like the unknown second child is likely someone viewers already know, possibly even someone who grew up with the Liars. Charlotte's biological sibling might be the one seeking revenge for her death, but there are other possibilities at play. Considering how much the show has been hyping up Jessica and Mary's rivalry, is it possible that her child is Alison?
Hear me out: there is a pattern. Jessica was apparently known for stealing everything Mary had, including her firstborn child. If Mary gave birth to another kid while she was a patient at Radley, why wouldn't Jessica take in that child too? The ages fit, and it would add another layer to the growing bond between Alison and Mary. Though there is no love lost between Mary and her sister, so there would be no reason for Mary to keep this information from Alison now, especially if she wants to stay close to her.
However, Alison isn't the only possibility. Mary's second child could be a brand new character whom we've never met. Then again, where's the fun in that? There are certain characters whose names come up every time something weird is going on in Rosewood and now that almost all of them are back in town, they're all possible new Drakes. Noel Kahn is clearly up to something now that he's returned; he's also the same age as the main crew of girls and he's always had a connection to the DiLaurentis family. Plus not too much is known about his family life, so he could easily be adopted.
Then there's Andrew Campbell, who was a popular guess for Mary's first child before fans found out it was Charlotte. Andrew is the right age, he's confirmed to have been adopted, and he's got a definite DiLaurentis/Drake look about him. However, there hasn't been any news that Brandon W. Jones, who plays Andrew, is returning for Season 7.
My guess is that Alison is Mary's child; her family is certainly full of enough secrets for that to be a possibility.