'Pretty Little Liars' Season 5 Episode 7 Spoilers: Will Aria Find the Truth about Bethany Young?

The mysteries in season five of "Pretty Little Liars" are piling up, and when one gets solved, another one crops up.

In the upcoming episode, titled "The Silence of E. Lamb", Aria will embark on a mission to find the truth about Bethany Young, the teenager who was found buried in Alison's grave.

The existence of a connection between Mrs. DiLaurentis and Bethany was discovered in the previous episode when Eddie Lamb, the nurse at Radley, gave Ezra a drawing of Bethany's that featured Alison's mother.

The painting showed Mrs DiLaurentis tending to her flowers while a demon is about to attack her.

Why Eddie gave the sketch to Ezra, and not Spencer, is still a puzzle. But the answer clearly lies in Radley, and this prompts Aria to go undercover to work as a volunteer at Radley on Tuesday's episode.

But solving the mystery behind Bethany's identity might not be an easy task, as the promo for "The Silence of E. Lamb" shows that Eddie is suspicious of Aria.

The promo shows Eddie wondering if he has seen Aria before, and she lies to evade further questioning.

"Did you volunteer for the reading program last year?" Eddie asks Aria in the promo for Tuesday's episode. "No," Aria lies. "No, this is my first time here."

But Eddie looks unconvinced, and it remains to be seen if Eddie remembers Aria from the number of times she has visited Radley to meet the other Liars.

It remains to be seen if Aria will uncover the relationship between Bethany Young and Mrs. DiLaurentis, but based on the episode synopsis, "she quickly hits a snag when she comes across an aggressive patient that may be the key to what the Liars are looking for."

In the meantime, fans of Pretty Little Liars have come out with a number of theories on who Bethany Young could be. And a popular thought is that she is somehow related to Wren.

A good number of fans believe that Wren and Bethany are siblings, and this might explain why Wren was always interested in what goes on at Radley.

Supporting the belief and explaining how Bethany ended up at the sanitarium, a fan wrote on Tumblr: "His father had some sort of mental illness and Bethany could have inherited it."

"Wren talked to Hanna about having an ambiguous loss and if Bethany is his sister it would certainly be one for him seeing as she first disappeared mysteriously and then was found murdered, Wren was left without closure (and seeks it as A)," the Tumblr post noted.