Factual error: On page 25, it mentions that the boa constrictor at the zoo winked at Harry. Snakes don't have eyelids at all, so it's impossible for them to wink.
Factual error: When Harry is with the Dursleys in the run-down shack, he realises that Tuesday is his birthday. However, in 1991, July 31st was a Wednesday.
Harry Potter and the Prisoner of Azkaban
Alice in Wonderland
Harry Potter and the Chamber of Secrets
Harry Potter and the Goblet of Fire
Harry buys the book "One Thousand Magical Herbs and Fungi", but later, the title changes to "One Hundred Magical Herbs and Fungi".
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A new menu and more - thoughts welcome...
25 biggest mistakes in classic Disney movies
First pictures of Josh Brolin as Cable for Deadpool 2
The biggest mistakes in Spider-Man: Homecoming