Okay, so let’s start off with some basic background family tree information. Starting with Jenna. We do not know her parents’ names. However, we know her father isn’t in the picture and her mother married Toby’s father, Daniel. Daniel was originally married to Marion and together they had a child, Toby. Marion was in Radley for whatever reason and died. So here’s my theory:
Let’s say Marion had a sister, Jessica DiLaurentis; and Daniel and Marion also had twins after Toby was born. Let’s say those twins were named Bethany and Alice. (Alice was the ghost girl who looked like the twin for Ali’s Halloween twin story.) I know Young is Bethany’s last name but maybe she changed it or Daniel is not the twins father; maybe Marion had an affair (those are common in Rosewood/maybe Bethany took her father’s last name rather than Cavanaugh) So we don’t know Bethany’s father, but let’s say Marion is 100% her mother. Marion and her husband OR Daniel come home to Bethany having killed Alice in the kitchen. Bethany is sent to Radley at a very young age where she ends up living most of her life in. Marion hides this from Toby. He doesn’t know where his twin sisters have gone to. He’s young too at this point, so he will probably believe whatever his parents tell him.
Marion may or may not have visted Bethany, but for whatever reason she was sent to Radley herself. Mental illness runs in the family. There, Bethany gets to know her mother a little better. Maybe when realizing it is her, she (the fragile patient) pushes Marion off the roof/out the window) for sending her to Radley and ruining her life.
Remember, Marion and Jessica may be sisters. This would make Bethany Jessica’s niece, hence “Aunt Jessie.” The other yellow dress little Ali found was probably for Bethany. “Daddy can’t know, or he will leave us.” I think Jessica has grew very fond of her niece, buying her clothes, taking her to the stables, letting her adopt a horse, etc. Surely Jessica is keeping this from her husband, Kenneth. Remember, Mrs. D was also on the board for Radley, probably to help protect Bethany. Now since Bethany is Jessica’s niece, that would make Bethany and Ali cousins.
So now that we are getting somewhere, Bethany writes Ali a letter thanking her for the invite to come to Rosewood for labor day weekend. Not quite sure how she got the letter, but let’s just say Ali and Bethany were plotting and Ali was trying to help Bethany escape from Radley the night Ali disappeared. So Bethany escapes and comes to Rosewood to meet Ali. That is who is on the phone with Mrs. D. She’s gotten a call about Bethany escaping. This is also why she doesn’t want Ali going out. Ali goes out anyway. Later, she’s hit with a rock. I think Bethany hit Ali with that rock. Mrs. D is all “what have you done?!” I think Bethany forced Mrs. D to bury Ali, who she thinks is dead. Later we find out she wasn’t and was pulled out by Mrs. Grunwald. Alison is pissed that Bethany did this because she thought they were cool. Turns out Bethany hated Ali and Mrs. D so she had been wanting to escape Radley for awhile to get revenge.
So now Ali wants to kill Bethany. This is all taking place at the time Spencer is chasing a blond through the woods with a shovel. She thinks it’s Ali, but it’s actually Bethany, trying to get back to Radley. Spencer hits her on the head with a shovel, again thinking it’s Ali, and walks away. Melissa sees all this going down, she too thinks it’s Ali. She buries Bethany alive, thinking she’s dead. Bethany suffocates.
OKAY, so where is Toby in all of this? He finds all of this out. He wants to avenge his sister and his mother. He wants to attack Ali and the liars. He’s heartbroken cause he doesn’t know if Bethany killed Marion, or if Mrs. D killed Marion. Either way, let’s say he thinks Mrs. D killed Marion. (Maybe she did? It could have been Bethany or Mrs. D) BUT Toby wants Ali and Mrs. D dead cause he thinks they’re responsible for Marion’s death. Toby is also blaming Spencer cause she hit his sister. That’s why he gets into a relationship with her to get closer to her so he can figure out how to hurt her. That explains Ali and Spencer. Let’s not forget how Ali made him take the fall for the Jenna Thing. Toby wants revenge for that as well. He’s secretly still working with Jenna.
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