Ariana Dumbledore, the younger sister of Albus and Aberforth Dumbledore, played a small but significant role in the Harry Potter series.
Her tragic story influenced the brothers for good and ill, ultimately serving as a source of inspiration and regret for her remaining family.
What Happened To Ariana Dumbledore?

At only six years old, Ariana illegally practiced magic in her family’s backyard. Three boys who spied on her through the hedges were both intrigued and scared by what they saw, so they confronted her.
When Ariana couldn’t show them the trick, meaning either that she couldn’t show them how to do it or couldn’t repeat it, they attacked her.
The attack had long-lasting effects on her. The trauma of the incident caused her to never willingly use magic again. Attempting to stifle it resulted in a sort of madness. As Aberforth said, “She was never right again.” Her father was eventually sent to Azkaban for seeking revenge on the boys who ruined her life.
Fearing that others would find out about Ariana’s unstable position and send her to St. Mungo’s, her mother moved them to Godric’s Hollow. Rumors swirled that she was imprisoned by her family out of shame that she was a squib.
Aberforth, while he was home from school, was able to calm Ariana when the madness took her and get her to eat when no one else could, sharing a relationship with her that Albus and their mother did not have. However, he wasn’t home when, at the age of fourteen, Ariana went into a rage that killed their mother.
Though Albus was about to embark on a trip around the world with Elphias Doge, he came home to attend the funeral and become the head of the household. He assumed responsibility for Ariana, even though he resented it, and even though Aberforth wanted to be the one to do it.
Encouraged to finish school by Albus, Aberforth allowed Albus to take care of Ariana. A few weeks passed until Grindelwald came into Albus’ life, distracting him from the care of his sister. Aberforth wouldn’t sit by as Albus made his “grand plans for the greater good,” with his new friend, neglecting Ariana in the process.
Aberforth returned home, confronting Grindelwald and Albus, saying Ariana was in no state to be dragged along as Albus pursued his dreams with Grindelwald to take over the magical and muggle world.
This confrontation became a violent battle which ultimately resulted in Ariana’s death.
Who Killed Ariana Dumbledore?
As the three of them were dueling, the anxiety and confusion became too much for Ariana.
Aberforth described her reaction to the battle vaguely saying, “she couldn’t stand it,” and “she wanted to help, but she didn’t really know what she was doing.” From this, we can assume that she started to fire off out-of-control magic.
Though it’s not exactly clear, it’s possible they tried to stop her. In the chaos, Ariana was killed by a runaway spell, and no one is really sure who was responsible.
How Old Was Ariana Dumbledore When She Died?
According to Aberforth, Albus took care of Ariana well for a few weeks before beginning to neglect her.
Rita Skeeter’s biography quotes Bathilda Bagshot as saying that Grindelwald and Albus parted two months into their friendship as a result of Ariana’s death.
This means that after their mother’s death in Ariana’s fourteenth year, it was somewhere around three months after the funeral that she died, putting her between fourteen and fifteen years old.
Conclusion
The story of Ariana Dumbledore is a tragic tale that haunted both Albus and Aberforth for the rest of their lives.
A sweet and timid girl turned mad with pent-up magic, her untimely death changed the course of her brothers’ lives and of the magical world as a result.