This Theory About What Really Happened to Dumbledore's Sister Will Make Your Head Spin

As one of the Harry Potter series' most important characters, Albus Dumbledore's early life was fraught with tragedy. Over the course of just a handful of years, his sister was attacked, his father was sent to prison, and his mother was killed in an accidental explosion caused by his sister Ariana. And then Ariana died in the crossfire of a duel between Albus, his brother (Aberforth), and Albus's then-best friend, Gellert Grindelwald.

The real truth of the events that transpired is still widely debated, but one question that's never been answered is a pretty major one: who actually killed Ariana Dumbledore?

First, some context on the sad story of Ariana Dumbledore. At just 6 years old, she was brutally attacked by three Muggle boys who spotted her doing magic. The event left her mentally unstable and scared to perform magic. Her emotions turned inward, creating what many fans assume to be an Obscurus, which is the bottled-up, dangerous energy of a child with magical powers (known as an Obscurial) who isn't allowed to practice his or her magic. Obscurus were explored in Fantastic Beasts and Where to Find Them, and there's justified speculation that Ariana was an Obscurial as a result of her childhood trauma with the Muggles.

Dumbledore's father, Percival, went after the Muggles who harmed his daughter, earning him a sentence in Azkaban. His mother, Kendra, moved the family to Godric's Hollow and kept Ariana hidden from the wizarding world, due to her uncontrollable magic. One of Ariana's magical explosions resulted in Kendra's death, leaving Dumbledore to take care of his family right after he graduated Hogwarts and was planning to travel the world with his close friend and confidant, Gellert Grindelwald — the man with whom he planned a "new world order" between the wizarding and Muggle worlds.

Albus's brother, Aberforth, felt that Dumbledore was neglecting Ariana as he pursued his ambitious path with Grindelwald, and their disagreement came to a head when all three wizards engaged in a violent argument that left Ariana Dumbledore dead. There's always been the implication that Grindelwald dealt the final magical blow that ended her life, but a new theory argues that a much darker sequence of events unfolded and that Dumbledore was actually to blame. Here's what it says:

Based on the nature of how the Elder Wand is passed from person to person (a wizard must win the wand), the theory argues that Ariana Dumbledore overpowered Grindelwald (who wielded the Elder Wand at the time) to protect Aberforth, thus winning its allegiance for herself. Based on that fact, if Dumbledore accidentally killed Ariana in the confusion of the duel, the Elder Wand's allegiance would have then shifted to him, which would explain why the wand answered to him in the future. More widely accepted theories of the wand's allegiance come from the belief that Dumbledore won it in the famous duel with Grindelwald much later.

"This is why Albus took so long to fight Grindelwald [later when he rose to power as a dark wizard]," the theory claims. "He knew that it would confirm that it was he who had killed Ariana. It did, and he lived with that for the rest of his life."

Live with it he did. Dumbledore is undeniably guilt-ridden for reasons that are never fully explained (think about his reaction to the Drink of Despair in Half-Blood Prince). This theory is also supported by his explanation in the book as to why he put on the cursed ring containing the Resurrection Stone.

Sorry for neglecting his family? Sorry for starting down a dark path with Grindelwald? Or sorry for sending out the curse that ended the life of his own sister? You decide.