The Tragic Lupin Detail Harry Potter Fans Don't Realize

Despite the fact that the original books were ostensibly written for children, the Harry Potter franchise features plenty of characters with terribly sad pasts, including the title character, an orphaned boy wizard who spends the early years of his life in an abusive household. However, you might be overlooking the true tragedy of one of the series' most important supporting players. Spoilers for Harry Potter ahead!

Remus Lupin, portrayed in the films by David Thewlis, is introduced during Harry's (Daniel Radcliffe) third year — in both the book and movie version of Prisoner of Azkaban — as Hogwarts' newest Defense Against the Dark Arts teacher, though his tenure is cut short when another faculty member reveals that Lupin is actually a werewolf. As it turns out, Lupin proves himself to be an invaluable presence in Harry's life, which is fitting, as he was once close friends with Harry's father James and godfather Sirius Black when they were all at school together.

Lupin eventually marries fellow resistance fighter Nymphadora Tonks (played in the movies by Natalia Tena) and starts a family when the two have a son, Teddy, but throughout his life, there's no question that Lupin carries a significant amount of trauma with him at all times. Beyond losing his best friends to Voldemort throughout the years — James and his wife Lily are murdered when Harry is a baby, and Sirius loses his life right in front of Lupin and Harry — Lupin's life is actually incredibly sad, for a reason that goes back to his childhood. Here's the tragic Remus Lupin detail that most Harry Potter fans never considered.

Though Lupin mentions this in the books, the Harry Potter encyclopedia Wizarding World confirms, in a piece about the horrifying werewolf Fenrir Greyback (the late Dave Legeno), that Greyback is responsible for biting a young Remus Lupin at just four years old and condemning him to a life with lycanthropy. Even worse, Greyback bit young Remus just to get back at Remus' father, Lyall, who had publicly insulted werewolves, and while Lyall never forgave himself, Greyback proudly bragged about his "accomplishment."

As time wore on, Lupin struggled to hold down jobs — and without help and kindness from Hogwarts headmaster Albus Dumbledore (Michael Gambon), he might not have even been able to attend Hogwarts at all. Knowing Lupin's struggle makes Greyback's lack of remorse even worse, as Wizarding World points out: "[...] according to Remus, Greyback 'regards it as his mission in life to bite and to contaminate as many people as possible.' The sheer number of Greyback's victims proved that the werewolf had not one scrap of regret for his wrongdoings, or the many lives he affected along the way. Seeing what Remus went through at Hogwarts illustrated just how far one bite could go in terms of both physical and emotional issues that lasted a lifetime."

Just to make matters more tragic, Lupin ultimately loses his life alongside his wife, Tonks, during the Battle of Hogwarts. Thankfully, his son Teddy, who doesn't share his father's affliction, is cared for by Harry himself, but it's still disheartening that one of Harry Potter's most lovable characters suffered so much throughout his life.

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