As Fantastic Beasts: The Secrets of Dumbledore promises to delve into Albus' (Jude Law) and Aberforth's (Richard Coyle) past, it can also explain Aberforth's lifelong obsession with goats, arguably the weirdest Dumbledore mystery in the Harry Potter saga. The third Fantastic Beasts movie will see Aberforth Dumbledore reunite with his older brother Albus as the latter is rallying everyone around him in his war against his friend-turned-foe Gellert Grindelwald (Mads Mikkelsen). It has been a long time since the brothers spoke to each other, and this reunion is bound to explore the more personal (and less expected) details of their relationship.
In The Goblet of Fire, Dumbledore says Aberforth "was prosecuted for practicing inappropriate charms on a goat." Dumbledore's notes in Tales of Beedle the Bard also point out that Aberforth's favorite story as a child was “Grumble the Grubby Goat,” and this was around the same time Aberforth used to throw goat dung at Enid Smeek. Goats are seen at the Hog's Head Inn where Aberforth works, and of course, Aberforth's Patronus is a goat, as seen in the Battle of Hogwarts. While the goat motif appears nearly every time Albus' little brother is mentioned, it's never clearly explained in the Harry Potter books or movies.
J.K. Rowling addressed Aberforth's goat fixation at a Q&A in 2007 (via The Leaky Cauldron): "But you know Aberforth having this strange fondness for goats if you’ve read book seven, came in really useful to Harry, later on, because a goat, a stag, you know. If you’re a stupid Death Eater, what’s the difference." She added that Aberforth's inappropriate charm was most likely designed to keep the goat's "horns curly and clean." As Fantastic Beasts 3 will see the Dumbledore brothers reunite for the first time in a long time, and considering the title of the movie, this is probably the best opportunity in the five-movie series to address the weirder sides of Aberforth. Rowling has been known to add fan service to the Fantastic Beasts movies (including the McGonagall plot hole in Fantastic Beasts 2), so it wouldn't come as a surprise if the third installment will shed some light on Aberforth's obsession with goats.
The Fantastic Beasts: The Secrets of Dumbledore trailer shows Albus meeting Aberforth in The Hog's Head Inn, Aberforth's bar in Hogsmeade. Aberforth asks Albus (with a sarcastic undertone) if he's "off to save the world." This goes to show exactly the fundamental difference between the brothers: while Albus has always strived for greatness, Aberforth preferred dueling to academic matters, Albus even hinting that he might be illiterate (which is why the goat charms scandal didn't bother him). But Aberforth is a good person, supporting Muggles even after his sister Ariana was attacked by Muggle boys. He eventually puts aside the bitter feelings left after Ariana died during a three-way duel between himself, Albus, and Grindelwald, and supports his older brother in his war against Grindelwald (and later, the war against Voldemort). The goat can be seen as a symbol of Aberforth's simple, but pure and kind nature.
The goat becomes an even more poignant symbol if seen as Aberforth's response to Albus' phoenix: perhaps Aberforth is mocking his older brother's love for the grandiose and is proud of choosing a simpler life. But the Dumbledores' relationship is more complicated than this. Fantastic Beasts: The Secrets of Dumbledore will most likely explore Ariana's tragic story in order to explain the feelings of blame and grief that both her brothers carry throughout their lives. But as the film delves into the darker sides of the Dumbledores' relationship, it can also bring in some comic relief to defuse the tense moments - Aberforth's goat obsession might just be the perfect means to an end.
