The Vampire Diaries
The Vampire DiariesFacebook/The Vampire Diaries

Caroline's attempt to cure her mother, Sheriff Forbes, by feeding her vampire blood takes a devastating turn in the next episode of "The Vampire Diaries".

The episode is titled "Prayer For the Dying" and a promo shows Sheriff Forbes being told about the death of another person who was fed vampire blood, and Caroline's mother accepting that she doesn't have much time left.

According to the official synopsis, Jo will try her best to save Sheriff Forbes but it is not clear if she will be successful in this endeavour. Executive producer of the show, Julie Plec, previously revealed that more than one person will die in the second half of the season, and now it seems that one of the casualties will be Sheriff Forbes - the character essayed by Marguerite MacIntyre.

But there is also the possibility of Caroline trying to turn her mother into a vampire. "Can you take someone dying of cancer and what happens if you were to turn them into a vampire? And that's one of the experiments that Caroline is going to be pondering in her head," Plec told Entertainment Weekly.

The episode is going to see Luke and Liv's father arriving to celebrate their birthday, and the twins will take the opportunity to convince him to let Kai and Jo merge. "After Tyler (Michael Trevino) finds out that the merge is happening sooner than he expected, he urges Liv to let him talk to her father," the synopsis reads. But, their well-laid out plans are going to spiral out of control, forcing one of the twins to take a difficult decision.

According to the executive producer, Bonnie - the witch who was missing in the mid-season premiere - may make her return sometime in the next three episodes. But, the Bonnie who returns will be a different person altogether.

"Bonnie comes back with a load of baggage," Plec said. "She was alone for a really long time. She got a little depressed." But one person she would have missed is Ian Somerhalder's Damon, and according to Plec, "They missed each other!"

"The Vampire Diaries" airs Thursdays on the CW.