When The Vampire Diaries started airing, no one anticipated that Caroline Forbes would go on to become one of the most popular characters on the show, but that's exactly what happened. Candice King's performance was a major impact on why Caroline went from a side character to one of the stars. However, there were other forces at play that influenced this change. One of them was the fact that Caroline underwent a serious transformation on the show from a ditzy young woman to a level-headed vampire.

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Those fans who read the books weren't familiar with this portrayal of Caroline. In the books, Caroline couldn't possibly be more different from her on-screen persona. That makes it fascinating to discover all the differences between the two versions of Caroline Forbes.

She Wasn't A Vampire

Damon feeding on Caroline in The Vampire Diaries.

Caroline is one of the few characters who became better people after their transformation to a vampire. She was more sympathetic, independent, and determined afterward. However, Caroline becoming a vampire is the show's invention. In the books, she changes into a werewolf, instead.

While Caroline of the show would no doubt manage to be a werewolf too, being a vampire somehow seems to fit her personality more.

Caroline And Stefan Don't Get Married

Caroline and Stefan married in season 8 of The Vampire Diaries

A major plot in the show is that Caroline and Stefan find their way to each other and become a couple even though Stefan had previously refused her in the first season and said that the two of them would never happen.

They even get married and love each other until Stefan sacrifices himself. This doesn't happen in the books, as Stefan is intricately tied to Elena all the way to the end, and he and Caroline never get together.

Caroline's Romance With Klaus

Caroline kisses Klaus in The Vampire Diaries.

A bit similar to Caroline and Stefan, she also doesn't fall for Klaus in the books—or, more precisely, the other way around. In the show, Klaus and Caroline spend a night together in the woods, but from there on they're friends and don't rekindle their romance. Considering that Klaus was even more ruthless and less sympathetic in the books, it makes sense that he and Caroline never had the type of bond they built on the show.

Caroline Marries Tyler

Tyler Lockwood hugging Caroline Forbes

One thing that both the show and the books have in common is that Caroline and Tyler dated, but their relationship wasn't so successful on the show. Tyler let his thirst for revenge consume him and eventually left Caroline alone, so they broke up.

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However, they managed to stick together in the books. Instead of marrying Stefan, Caroline married Tyler, and they even had two children together because, s a werewolf, Caroline was able to have children, unlike vampires.

Her Friendship With Bonnie And Elena

The Vampire Diaries Caroline hugs Elena in school

Despite her shortcomings, Caroline is much more sympathetic on the show than she was—for the most part—in the books. For one, she isn't as openly antagonistic toward Elena as her book counterpart. In the books, Caroline and Elena used to be childhood friends but when they grew up, Caroline started hating Elena. As a result, while she's friends with Elena and Bonnie on the show, that's not the case in the books.

She Looks Different

Elena and Caroline in The Vampire Diaries

A lot of The Vampire Diaries characters had their looks changed on the show, and Caroline is one of them. With her blonde hair, blue eyes, and pale skin, Caroline looks very much like Elena in the books.

However, Caroline's book counterpart was much different. She had auburn-red hair in the books, as well as green eyes and bronze skin. She was still very beautiful just like on the show, but her overall appearance was vastly different.

Her Family Is Different

Caroline Forbes and Sheriff Liz Forbes in The Vampire Diaries

All fans of the show will know that Caroline lived with her mom Liz and their dad had left the family years ago. Her family situation was a bit different in the books, though. Most notably, Caroline also had a younger brother named Daniel.

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She's an only child on the show, though. As previously stated, while Caroline does act as a mom to Alaric's daughters on the show, she only had biological children in the books, a daughter Brianna and a son Lucas.

A Different Set Of Powers

Caroline gets a letter from Klaus on The Vampire Diaries

Caroline turned into a vampire on the show, and, as such, she also gained the usual vampire powers, such as super strength, speed, and the ability to compel people. In the books, though, Caroline was possessed by a being called malach which gave her supernatural powers too. But, since it was an infection, Caroline had a hard time dealing with this. When Caroline got pregnant with Tyler, she turned into a werewolf and became a werewolf and malach hybrid.

No Relationship With Damon

Caroline and Damon hug in The Vampire Diaries.

Caroline's romance with Damon on the show was rather disturbing, so it's perhaps good it didn't appear in the books. Damon used Caroline as a blood bank, he had her try and push Stefan and Elena apart and tried to kill her in the end.

In the books, they didn't date, and the first time Damon had a major impact on Caroline's life was when he took back Elena's diary that Caroline had stolen from Elena and wanted to use to get back at her former friend.

She Accused Matt Of Being The Father Of Her Children

Caroline and Matt on stage in The Vampire Diaries.

The fact that Caroline wasn't such a nice person in the books—at least not initially—is also well demonstrated by the fact she accused Matt of being the father of her children. That, however, wasn't true, and it put Matt in trouble. Caroline later admitted the truth to her friends, but not before they confronted her about it.

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