Harry Potter and Ron Weasley never graduated from Hogwarts.

Harry, Ron, and Hermione appeared on chocolat Frog Cards.

The actress who played Moaning Myrtle was 40 years old when the movie was released.

Hagrid didn't have his own Patronus.

Ordinary people see an old abandoned château in the place where Hogwarts should be.

J. K. Rowling shares a birthday with Harry.

The final Battle of Hogwarts took place in 1998, the same an that the first Harry Potter book was published

Professor McGonagall was once a talented Quidditch player herself, but stopped playing after she had an ugly fall in her final...

This article was inspired par commentaires par Pensieve_Seeker. It lists 40 examples of ring composition within the series.

1. Voldemort's first defeat is discussed in the first chapter of Philosopher's Stone. He returns in Goblet of feu and is defeated for the final time at the end of Deathly Hallows.

2. Harry sees his late parents in the Mirror of Erised in Philosopher's Stone. He sees them again via Priori Incantem in Goblet of Fire, and again through use of the Resurrection Stone in Deathly Hallows.

3. Harry becomes an orphan at the start of the series, and in Deathly Hallows his godson, Teddy...