Template:AP-1473-1490s

Adyelya Petrova (Cyrillic: Адьельа Петрова) was born into a noble and wealthy Bulgarian family on June 5, 1473 alongside her younger twin sister Katerina Petrova. In 1490, when Adyelya and Katerina were about 16 or 17 years old; Katerina had gotten pregnant by an unknown man, specifically a Traveler. This caused Katerina to be disowned for the shameful birth of a daughter out of wedlock. Adyelya was also disowned as her parents didn't like that she supported Katerina's pregnancy and didn't see anything wrong with it, this made her parents fearful that she'd do the same thing Katerina did. Adyelya's niece was carried to term by Katerina but only seconds after her niece's birth, Adyelya and Katerina's father took the child away and gave her to another family; claiming to Katerina it would be better for both of them to never see one another. This caused both sisters to become devastated, but mainly Katerina, and the two were banished to England.

In 1491, Adyelya and Katerina met an English man; whom Adyelya caught the attention of and vice versa. They had a short term relationship that resulted in Adyelya getting pregnant with a daughter. He left her upon finding out about the pregnancy. Which told Adyelya, that the man only liked her for her looks. Later in the year, she successfully had her daughter who was carried to term.

In 1492, she and Katerina met Trevor, who introduced them to Lord Elijah, who in turn introduced them to his younger brother, Lord Niklaus. Katerina ended up being attracted to Klaus, but Adyelya wasn't attracted to either brother but did become close friends with their sister; Lady Rebekah. Then Katerina found out that Klaus was planning on using her as a sacrifice to break the Hybrid Curse placed on him. Katerina, along with her sister and niece, escaped with the help of Trevor, who had fallen for Katerina. He led their pursuers astray and told them to go east to a cottage in the woods where they would be safe. When they arrived at the cottage, Adyelya and Katerina met a vampire named Rose.

When Rose found out that and Katerina had escaped from Klaus with the moonstone as well as dragging her sister and niece along with her; she locked them in a room and told them that she would take her, her sister, and her niece back to Klaus as soon as the opportunity arose, not wanting to suffer Klaus' wrath. Katerina tried to commit suicide by stabbing herself with a knife and then stabbing her sister after, saying she and Adyelya would rather die than go back to Klaus, but Rose force-fed them some of her blood to heal them. When Rose turned her back to confront Trevor, Katerina hung herself with a length of rope but before that, she snapped her sister's neck. Later, when Katerina woke up in transition, Trevor asked why she did it and claimed he would have helped her, her sister, and her niece live. Katerina responds by saying that he would have been able to help them run and that running was never going to be enough.

Rose then explained to Trevor that Katerina used him to escape with her sister and niece, and, knowing Klaus would find out their role in the escape, Rose attempted to kill Katerina and Adyelya with two stakes. Katerina used the owner of the cabin as a shield, which resulted in her death. Katerina, as well as Adyelya, then gave in to their instincts and drained the little old lady, completing their transitions into a vampire. Katerina then threw the body towards Rose and Trevor and fled into the night. Adyelya and Katerina returned to Bulgaria in the later months of 1492 to find their entire family brutally slaughtered by Klaus. They knew he had done it as revenge for Katerina's escape and subsequent transition. They were last seen weeping over their mother's dead body.

Katherine may have stolen the spell for making Daylight Amulets from Esther's grimoire before fleeing from Klaus as this may explain how Emily was able to make Katherine, Alice, Neda, Bethanne, Pearl, Anna and Harper daylight rings and her a necklace in 1864.

Sometime during 1498, Alice and Katherine returned to Bulgaria after escaping from Klaus. Katherine searched every village and cottage for her daughter, Nadia Petrova, who was eight at the time, but had no luck in finding her.