Elena's surname is taken from her adoptive parents, though her biological father had the same surname. But Elena is descended from Katherine through her biological mother, Isobel. Either way, Elena took her father's surname, not that of an ancestor from nearly five hundred years ago.
Elena Gilbert (3rd Petrova Doppelgänger): Elena was born on June 22, 1992, in Mystic Falls, Virginia. She was the biological daughter of John Gilbert and Isobel Flemming, and was therefore a descendant of Katerina Petrova, to whom she bears a striking physical resemblance.
Katerina Petrova (a.k.a. Katherine Pierce, 2nd Petrova Doppelgänger): Katerina Petrova (Bulgarian and Russian: Катерина Петрова) was born June 5, 1473 in Bulgaria.
Much of Elena's story revolves around her relationships with vampires Stefan Salvatore and his older brother, Damon. It is revealed that Elena is a Petrova Doppelgänger (like Katherine, Amara and Tatia), which is thus responsible for her being identical to her ancestor, Katherine Pierce (née Katerina Petrova).
The Petrova Doppelganger is one of the most important and significant characters in the history of The Vampire Diaries and The Originals. Tatia is the first-known Petrova doppelganger, and her blood was used by Klaus' mother, Esther, to turn her children and husband, Mikaelson, into the first vampires.
Throughout The Vampire Diaries
In the season four finale of The Vampire Diaries, Graduation, Katherine slept with Niklaus Mikaelson and conceived her daughter, Adyelya.
Nadia Petrova (Bulgarian: Надя Петрова) was a major recurring character of The Vampire Diaries. She was a vampire and a member of The Travelers who was Katerina Petrova's daughter, making her an ancestor of Elena Gilbert and a descendant of Amara.
Nadia Petrova (Bulgarian: Надя Петрова) is a Vampire and a member of The Travellers. Nadia is also the daughter of Katherine Pierce and Markos. Nadia had spent the last 500 years searching for her mother. She is not very well accustomed to modern American culture and knows about the story of Silas, Amara and Qetsiyah.
Adyelya Petrova (Bulgarian: Адиела Петрова), more commonly known as Alice Pierce, is a witch of the Traveler sub-culture and a former main character of The Vampire Diaries. She was also the second-known Petrova doppelgänger of Ismene. In 1490, Alice and her sister were disowned by their father.
Tatia. The first Petrova doppelgänger, Tatia, lived during the late 10th/early 11th century. Amara had no children, so Tatia was linked to Amara though a child of one of Amara's siblings.
The term "Petrova Doppelgänger" comes from the last name of Katherine Petrova, the second doppelgänger of Amara. It is a term used by those who strove to find Katherine's doppelgänger and once discovered, directly referred only to Elena.
The Curse of the Sun and the Moon was bound with Petrova blood. And the Petrova doppelganger was created to undo the spell. Thus, Klaus needed Katherine to drain her blood as a sacrifice to break the spell.
The next doppelganger introduced is Katerina Petrova, a.k.a Katherine Pierce, born in 1473. Before she turns into a vampire to save herself from Klaus, she gives birth to a daughter, Nadia Petrova. It is assumed Nadia also delivers a child before she becomes a vampire, as the Petrova bloodline continues.
Katerina Petrova was born into a somewhat wealthy family in Bulgaria in the late 15th Century. Katerina had a daughter in 1490, however, the two were separated at birth. Katerina became a Vampire in 1492, turned by Rose-Marie's blood.
Isobel was a member of the Petrova Family and a former relative of the Saltzman Family due to her marriage with Alaric. She was also a relative to the Gilbert Family, as she was Elena's biological mother.
At the end of the second season, Adyelya is living with Katherine who seeks refuge with the New Orleans witches (who have become her allies), and by the end of the third season, she is living with Katherine on the road. By the fourth season, she lives with Katherine and the Mikaelson Family at the Abattoir.
Season Five. In the season premier, The Originals episode, during the summer Klaus--as well as Elijah, who follows his brother to New Orleans--is lured away to the French Quarter in New Orleans, where it is revealed by Sophie Deveraux that Katherine is pregnant with Klaus' unborn child (Adyelya Mikaelson).
Silas is the second oldest male character in the series universe (after Arcadius who is over 1,000+ years older than him), being 1,000+ years older than the oldest male Original Vampires such as Elijah and Klaus.
Both Isobel and Katherine are distantly related to each other by blood. Isobel bore Elena Gilbert, Katherine's doppelgänger. Both Isobel and Katherine slept with and dated Damon Salvatore. Katherine also sired Damon as a vampire, but Damon also sired Isobel decades later.
Nadia's father was a Traveller, not Klaus. The only child Klaus ever had was Hope. And no, Klaus and Elena are not related. But Nadia is Elena's ancestress.
In 1864, Stefan was turned into a vampire after being shot by his father, Giuseppe, along with his brother, Damon with Katherine's blood in his system, before accidentally killing his father during a visit to tell him that he was going to let himself die. Answer (1 of 2): She is from Niklaus Mikaelson's blood line.
To save Caroline, Tyler Lockwood bites Nadia in No Exit. They were the only vampires Tyler bit during his time as a hybrid. Caroline survived this encounter by ingesting Klaus Mikaelson's blood. Nadia died because of this encounter due to not having access to Klaus Mikaelson's blood or some sort of werewolf-bite cure.
While many of the characters are new and delving into their own narratives, there's one in particular from Legacies who got everyone talking. Prepare yourselves for this one: Damon and Elena have a daughter. And her name is Stefanie Salvatore.
Due to her child being born out of wedlock, Katherine's baby was taken away before she could even hold her. Human Katerina would have had misgivings about losing her baby, but not so soon after she was born.