All four mistakes that occurred in the Harry Potter 20th Anniversary: Return to Hogwarts reunion special explained. It’s hard to believe it’s been a little over two decades since the first film in the book series' big screen adaptation, Harry Potter and the Sorcerer’s Stone, was released. For the first time since the eight-film franchise ended, the cast of the Harry Potter movies gathered together once more to discuss the beloved magical universe and their experiences filming.

The reunion special premiered on HBO Max on New Year’s Day and brought together many of the actors who played the beloved characters from the Wizarding World of Harry Potter, though author J.K. Rowling was absent save for archival interview footage. While the Golden Trio — Danielle Radcliffe (Harry Potter), Emma Watson (Hermione Granger), and Rupert Grint (Ron Weasley) — were the main draw of Harry Potter 20th Anniversary: Return to Hogwarts, they were joined by a plethora of other co-stars from the franchise. The retrospective provided the actors a chance to reminisce about their time working on the film series, pay tribute to Harry Potter actors who have died, and reveal a few intriguing behind-the-scenes details like on-set crushes (Watson says she “fell in love” with Tom Felton).

Related: Where Was The Harry Potter Reunion Filmed? The Major Locations Explained

Harry Potter 20th Anniversary: Return to Hogwarts offered a large dose of nostalgia for longtime fans of the franchise, allowing viewers to revisit the Wizarding World alongside the actors who portrayed characters who are now forever embedded in pop culture. And while Harry Potter’s HBO Max reunion was special in many ways, it wasn’t completely free of errors. Here are the four biggest mistakes and oversights from Return to Hogwarts, including an In Memoriam slight.

Emma Roberts’ Photo Was Used Instead Of Emma Watson’s

Harry Potter Reunion Emma Roberts Emma Watson

When the cast of the Harry Potter franchise reunited, Danielle Radcliffe, Emma Watson, and Rupert Grint talked about their experiences filming, fame, and being cast as Harry, Hermione, and Ron, respectively. They discussed what it was like for them to play such iconic characters and touched upon their personal ties to the franchise. As they did so, photos were displayed of them as kids. But rather than ensure all of the photos were of the cast, the editors of the Harry Potter 20th Anniversary: Return to Hogwarts actually used a picture of actress Emma Roberts (American Horror Story) as a child sporting Minnie Mouse ears. As it turns out, Roberts previously posted the photo to her Instagram. An eagle-eyed fan on Twitter picked up on the mistake and it caught the attention of HBO Max reunion’s producers, who have since released a statement admitting to the error. It’s unclear how the photo of Roberts managed to slip by editors entirely unnoticed, but the error has been confirmed to be fixed by the reunion special's producers.

James & Oliver Phelps’ Names Were Switched In Harry Potter Special

James and Oliver Phelps giving an interview in Return to Hogwarts Phelps twins James Oliver

James and Oliver Phelps played Ron’s twin brothers, Fred and George Weasley, for all eight Harry Potter films. The Phelps twins reunited with the rest of the cast to discuss the Harry Potter franchise. However, their names were mislabeled and they were named the wrong way around. It was Oliver Phelps who pointed out the mistake in an Instagram post. Tom Felton took credit for the name-swapping error, joking in Phelps’ comments section that the switch was instigated by him.

All told, this is one of the funnier errors from the Harry Potter 20th Anniversary: Return to Hogwarts reunion considering Fred and George were always pretending to be each other in the movies and books to confuse people and their mother, who occasionally got their names wrong along with so many others. It’s unclear whether or not the confusion between the Phelps twins was intentional, but it seems rather apt considering their characters’ history within the world of Harry Potter. The mistake, like Watson’s photo, has also been corrected and the Phelps brothers rightly named in HBO Max’s Harry Potter special.

Related: Harry Potter Reunion: 15 Biggest Reveals & Secrets From Return To Hogwarts

Mike Newell Calls Goblet Of Fire Longest Harry Potter Book

Harry Potter Goblet Fire Robert Pattinson Daniel Radcliffe

Director Mike Newell — who helmed Harry Potter and the Goblet of Fire and admitted he cracked his ribs wrestling one of the Phelps brothers on-set — called the fourth book the longest of the seven. However, it’s actually Harry Potter and the Order of the Phoenix, the fifth in the seven-book series, that reads the longest. Harry Potter and the Goblet of Fire, at 636 pages, is the second longest in the series; meanwhile, Harry Potter and the Order of the Phoenix is 766 pages long. Newell can be forgiven for the oversight considering he directed Goblet of Fire which was, to be fair, the first Harry Potter film to be adapted from a book that was more than 300+ pages long. The first two Harry Potter books were at 250 pages or less and Goblet of Fire had a lot of content and new characters — including the students from Durmstrang and Beauxbatons — to introduce to the magical universe.

Harry Potter Reunion's In Memoriam Left Out Berry The Dog

Since Harry Potter and the Deathly Hallows: Part 2’s release in 2011, several of the actors who appeared in the franchise have sadly passed away — Alan Rickman, who played Professor Snape, Helen McCrory, who played Draco Malfoy's mother Narcissa Malfoy, and John Hurt, who played Ollivander, among them. During the Return to Hogwarts reunion special, the Harry Potter cast paid tribute to all of the late actors, discussing their memories of them and how they influenced the younger cast especially (Tom Felton became visibly emotional when talking about McCrory).

However, the tribute section of Harry Potter 20th Anniversary: Return to Hogwarts forgot to mention Berry, the black German Shepherd that played Sirius Black’s Animagus form in Harry Potter and the Prisoner of Azkaban. Granted, Berry wasn’t a person or anything, but the canine was still a big part of the Harry Potter films and played a role in advancing Sirius’ storyline, in particular. It would have made a world of sense to include him in the In Memoriam section of the HBO Max reunion special.

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