Unfortunately, fans of "The Vampire Diaries" will have to wait until April to find out whether or not Lily Salvatore will help trigger Stefan's humanity switch, and if she, herself, can be trusted.

Last week fans learned that Lily, aka Mama Salvatore, was a ripper who was banned inside of a 1903 prison world by the Gemini Coven after she slaughtered thousands of innocent people, notes Hypable.com.

A preview of the next all-new episode, entitled "I Never Could Love Like That," shows that Damon will reunite Lily with Stefan in hopes that she will prompt Stefan to flip his humanity switch back on.

"She is a tool to get Stefan's humanity back," Damon tells Elena referring to Lily in the promo.

Damon also gives his mother a little pep talk before she faces Stefan.

"You can do this. All you have to do is just try," he says.

The promo ends with Damon and Lily walking into the bar.

"Who's that?" asks Caroline. "It's my mother," responses Stefan in utter shock.

During a recent interview with Entertainment Weekly, Annie Wersching teased that her character, Lily, will have a hard time establishing a normal relationship with her sons, Damon and Stefan, after faking her own death and abandoning them for centuries. According to her, part of the problem stems from her own feelings of extreme guilt and regret.

"She has a lot of torment inside of her ... And then adding this guilt that she feels for what the boys think of her and think that she did to them, [it] really messes with her."

Wersching also revealed that Mama Salvatore will have trouble adjusting to her present-day life and bonding with her sons.

"They do eventually become their own version of a mother-son relationship," she added.

According to The Hollywood Hills, the synopsis for "I Never Could Love Like That" states:

"With their humanity turned off, Stefan and Caroline begin wreaking havoc at Whitmore, leaving Damon to come up with a risky plan involving Lily. After rushing to help Jo treat victims of Stefan and Caroline's latest killing spree, Elena discovers Jo is pregnant, prompting her to reevaluate her own life as a vampire.

Season 6, Episode 18 of "The Vampire Diaries," entitled "I Never Could Love Like That," will air Thursday, April 16 at 8 p.m. ET on The CW.

Watch preview videos below.