Legacies: Caroline's Secret Mission Is Tied to a Major Vampire Diaries Plot

WARNING: The following article contains spoilers for "Mombie Dearest," the latest episode of Legacies.

When The CW spun Legacies out of The Vampire Diaries and The Originals, many fans were eager to see some of their favorite characters return to The Salvatore Boarding School for the Young and Gifted. Though "Mombie Dearest" marked the brief return of Alaric's first love, Jo Laughlin (Jodi Lyn O'Keefe), viewers also got valuable information regarding the whereabouts of Josie and Lizzie's other mother, Caroline.

The episode began with the twins learning Caroline wouldn't be able to make it to their Sweet Sixteen birthday party. They were understandably upset, which is what caused them to confront Alaric in his office, only to find their revived biological mother. Jo was ultimately sent back to the Afterlife, but not before discussing with Alaric what happens to Josie and Lizzie when they reach the age of 22.

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"Do they know what happens when they turn 22?" Jo asked? "No, not yet. And we don't want them to know until we've exhausted all our options," Alaric replied. "That's why Caroline missed their birthday. She's following some lead." As fans of The Vampire Diaries and The Originals are keenly aware, once Josie and Lizzie turn 22, they'll be forced to undergo The Merge.

The Saltzmans are members of the Gemini Coven of witches who participate in The Merge ritual that occurs on a set of twins' 22 birthday. The ritual sees the stronger twin absorb the magical powers of their weaker sibling, leaving the weaker one dead and the survivor the new leader of the Gemini Coven. Since Jo is the twin sister of Kai, the two were supposed to perform the merging. However, Kai's violent tendencies led him to murder the rest of his siblings and force Jo to agree to the ritual.

What Kai didn't realize is Jo hid her magical abilities in a knife. Once The Merge failed, Kai was trapped inside a Prison World where he remained until Alaric and Jo's wedding day, where he murdered Jo before the vows were complete.

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Josie and Lizzie were transferred to Caroline, which is how they survived Jo's death. And now knowing what's in store for Josie and Lizzie in six years, Caroline has set off on a quest to find a way to prevent her daughters from having to take part in a ritual that has proven time and time again to rip families apart. There is plenty of time before The Merge should play a significant role in Legacies, but introducing it now in the show's freshman season is a nice nod to the dedicated Vampire Diaries who continue to watch and support Legacies.

Airing Thursdays at 9 p.m. ET/PT on The CW, Legacies stars Danielle Rose Russell as Hope Mikaelson, Jenny Boyd as Lizzie Saltzman, Kaylee Bryant as Josie Saltzman, Quincy Fouse as Milton Greasley/MG, Aria Shahghasemi as Landon Kirby, Peyton Alex Smith as Rafael Waithe and Matt Davis as Alaric Saltzman.

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