When Caroline wakes up to a noise, she descends the stairs to check it out. Leaving her presumed cured mother, Caroline gets startled by Colin, a patient at the hospital, where Caroline helped by feeding him blood.

From the looks of Colin spewing blood, Caroline did not help him at all. Later we find out that, Caroline's vampiric blood just sped the spread of the cancer.

Relaying this information to Stefan, Caroline gets her mother to the hospital, where Jo works. Hoping for better results, Caroline receives the bad news and disappears with her guilt.

Stefan finds Caroline at a flower shop. The normally bubbly vampire cannot decide between which floral arrangements she should have at her mom's funeral. Stefan shares a story of missing out on spending time with his mother before she passed away because he wants Caroline to use the time to spend with her dying mother before it was too late.

At the hospital, Elena visits Sheriff Forbes's room. Elena reveals to Liz the truth about her condition and promises her best friend's mom that she would find Caroline, so that she doesn't feel burdened with the guilt.

Meanwhile, Damon makes a deal with Kai to take the “magic” out of Liz in order to stop the spread of her cancer from speeding up.

Nevertheless, Liz suffers from a heart attack. When Caroline's mom flatlines, Elena tries to save her without luck. When Damon gets a doctor to assist Elena, his attempt is pointless.

While Liz looks to be dying, she sees in the other side, a glimpse of Caroline after packing some belongings in a suitcase.

Caroline and Stefan walk into the room. Hope seems to be lost until Liz miraculously wakes up.

Elsewhere, Kai finds Jo to merge with her only to be interrupted by Luke, who sacrifices himself for his family by merging with Kai.

At the end, who is the stronger of the two?

Watch a sneak preview of next week's episode:

Tune into The Vampire Diaries on Thursdays at 8 p.m. on The CW.