How Is Jason's Twin Big A on 'Pretty Little Liars'? Here Are All The Ways We Should Have Known

Tuesday's season finale of Pretty Little Liars brought the reveal of Big A. But then, in true PLL fashion, the reveal left us with so many more questions than answers. Turns out that there's been another DiLaurentis this whole time — Jason has a twin. Not only that, but Jason's twin is named Charles, and he's Big A. If you're mind's swirling from all that information, don't worry. It might take a few days (or years) to process exactly what happened during the PLL finale, "Welcome to the Dollhouse" and now I'm kind of kicking myself over the fact that I didn't pick up on this sooner. But let's slow down, and take this piece by piece.

For starters, what exactly happened during the PLL episode? Spencer — clever girl — figured out one of Big A's anagrams, and realized that it spelled out "CHARLES." The Liars then managed to tamper with the generator in their dollhouse prison, and made the lights flicker, cut all the power, and then booked it the hell out of there. Then of course, Spencer, needed to take a little detour and check out this Big A a little bit more for herself. She stumbled upon a room with an old family movie in it, and after hitting play, it revealed some heavy stuff.

Like what? In the old family movie we see a happy family: mom and three kids. Mrs. DiLaurentis bends down, holding a baby, and tells the two boys playing to come and kiss their sister. The tiny baby is Ali, and the boys? Jason and this new found Charles.

The Books Kind of Predicted This

If you're familiar with the PLL series by Sara Shepard, you'll know that the Big A twist in the novels is that it's Ali who has a twin, and causes all sorts of chaos. The two twins — Alison and Courtney — impersonate one another, and Courtney winds up in a mental institution by Alison's doing. Then Ali kills her. It was thought that Ali might end up with a twin on the TV show, but clearly that's not the case. However, they're still keeping that twin idea it in the family. It's just Jason now.

Mrs. DiLaurentis Was On The Radley Board

There was never any real concrete reason as to why she was on the board of the mental facility. The big question now is — uh, where was Charles been all these years? Might he have been at Radley? If her son happened to be detained there, that would be a reason for Mrs. DiLaurentis to be invested in Radley's future.

There's also a scene in the Season 4 finale, "A is for Answers" where Mrs. DiLaurentis takes a phone call from Radley about someone escaping custody from there, and she's pretty panicked over it. More than likely, this was Charles.

About the Night Ali Disappeared...

That Radley phone call happened on the night Ali disappeared. Mrs. DiLaurentis never revealed to the police who it was that hit Ali on the head that night, and then of course, Mrs. DiLaurentis buried the body. Why would she do such a weird thing? A mother will do anything to protect their own children — even one that's happened to escape from Radley. It's shaping up to look like it was Charles who hit Ali that fateful night.

The Hastings Still Have So Many Secrets

Back up a second, and remember the fact that Jason is also Spencer's half-brother. That would make Jason's twin Spencer's half brother, too. Unless Mr. Hastings is completely clueless about this, he's got to know that there are two boys out there. The Hastings seem to want to stop at nothing to make sure that their family is protected, no matter what the cost. Also, Mrs. DiLaurentis never trusted the Hastings. Maybe it was was the family next door who sent her son away from her.

Jason and Ali's Relationship

Jason breezes in and out of Rosewood all the time. Was it because he was visiting Charles? Or did he just not want to stick around town because of bad memories of the past? Jason might not have known about Charles to begin with — hey, if they were still kids when Charles went MIA, Jason really might not have known anything when the series picks.

On top of that, Jason and Ali never got along. Their relationship was always painted as very strained. Ali doesn't seem to know anything about having another older brother out there somewhere, and there's probably a good reason for that. Could Charles have done something to hurt Ali as a kid, which is why he was sent away in the first place? Now Charles is trying his hardest to kill her, for the childhood she clearly took away from him.

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