Legacies has prided itself on setting the show apart from both The Vampire Diaries and The Originals, but at the end of the day, it's still a spin-off set in TVD Universe, which makes explaining away some characters' absences a little difficult.

Caroline Forbes (Candice King), for example, is a character whose absence is of particular interest to many fans considering she not only founded The Salvatore School with Alaric Saltzman (Matthew Davis), but also co-parents two children with him: Lizzie (Jenny Boyd) and Josie (Kaylee Bryant). So far Caroline's absence has yet to be addressed in the show, but according to the cast that won't be the case for much longer.

"It's definitely something that we talk about constantly just because if you have a mother that worked with your father to build up this school that you're now living in, and it's such a big part of your life, her absence is constantly felt," Bryant tells TV Guide.

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Adds Boyd: "We definitely touch on that as well, how much it affects the girls. In one of the episodes, Josie is explaining about Lizzie and how volatile she can be, and she says, 'You know, we just really miss our mom and she hasn't been around and that's really hard.' It really affects them in a negative way."

TV Guide has also learned that the twins will be throwing a Sweet Sixteen party in the first half of Season 1, for which Caroline will be conspicuously absent. Josie and Lizzie won't exactly be thrilled that their mom has skipped out on their big day for what is supposedly a simple recruiting mission for new students, but what they don't know is that is merely a cover for Caroline's true mission, the nature of which Alaric is well aware of and keeping secret from their daughters.

"Alaric is very, very well aware of where Caroline is," says Matt Davis. "We'll also learn more about what she's really doing as the season progresses."

There's clearly more to the story that we have yet to explore, but it would obviously take something pretty huge to pull Caroline away from her daughters for such an extended period of time. Considering showrunner Julie Plec teased at the Television Critics Association summer press tour that Caroline's trip abroad would have something to do with "the long-term survival of their daughters," we've got a feeling it's something to do with their Gemini coven background.

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The Geminis are best remembered from The Vampire Diaries as a coven of witches with a ritual called The Merge, in which twins would be forced to undergo a ceremony at the age of 22 where the stronger twin would absorb the other, effectively killing their sibling. We've already seen some sibling rivalry emerge between Josie and Lizzie, and Caroline and Alaric would naturally want to seek out a way to avoid any chance that their daughters would be put through this ritual.

Could Caroline be off on a Gemini-related mission? Only time will tell!

Legacies airs Thursdays at 9/8c on The CW.

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