The Vampire Diaries has many complicated relationships between the various founding families of Mystic Falls and others.

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It turns out Nora (Scarlett Byrne) was not kidding around with Caroline (Candice King) when she dished Valerie (Elizabeth Blackmore) is not as nice as she was acting.

It turns out Stefan (Paul Wesley) has previously met Valerie years and years ago, which more details will be revealed about in "Age of Innocence," which airs this Thursday.

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The CW Television Network's YouTube channel released a sneak peek into the episode, which can be watched below that shows Stefan having a chat with Lily (Annie Wersching).

They initially make small talk about driving more so on her part than his and then Stefan makes it seem as though he and Damon (Ian Somerhalder) are at odds, which seems to intrigue Lily since it is obvious she wants them to hate each other.

Before diving into the fighting with Damon, Stefan addresses Lily about her heretics abusing Caroline since she is still very much their prisoner.

"Listen, you need to tell those spoiled brats living in my house to stop torturing Caroline," Stefan tells her, which leads to her telling him to give Damon the memo that he needs to stop killing them.

That obviously leads to Stefan planting the seed that they're fighting, which would make Lily happy. So Lily then agrees to talk to her three female heretics since they've been rather brutal toward Caroline so far.

"Is one of those girls named Valerie Fell?" Stefan then asks Lily, which leads to her admitting she is the reason he and Valerie ever met.

"I knew Valerie years before you did. She worked in my TB ward," Lily explains to him, adding, "After I turned I took her under my wing. If memory serves me you didn't meet her until 1863."

That bit of information sparks intrigue in Stefan since he has no idea how his mother would know when he met Valerie and it turns out she had everything to do with it.

"Because Stefan, I sent her to you," Lily states.

The Vampire Diaries airs on Thursdays at 8 p.m. ET on The CW.