Hermione Jean Granger is a fictional character in J. K. Rowling's Harry Potter series. She first appears in the novel Harry Potter and the Philosopher's Stone, as a new student on her way to Hogwarts. After Harry Potter and Ron Weasley save her from a Troll, they become best friends. She’s described as a quick-witted, level-headed person, with a great passion for learning.

Hermione was originally intended to have a sister, but the planned sibling did not make an appearance in the first Harry Potter novel and, as Rowling noted, it ‘seemed too late’ to introduce the character after all of that. Rowling confirmed in a 2004 interview that Hermione is an only child.

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