After Sirius (in his Animagus form) drags Ron into the secret passage under the whomping willow, this character presses the knot on the trunk to stop the tree moving so that Harry and Hermione can enter the passage.

Albus Dumbledore's siblings

The death of Albus Dumbledore.

Doe

This object is the portkey that left Stoatshead Hill, Ottery St. Catchpole for the Quidditch World Cup.

This creature is in Professor Lupin's office when he and Harry have a cup of tea while Ron and Hermione are at Hogsmeade.

Narcissa Malfoy's sister
Sirius Black's cousin

The death of Sir Nicholas de Mimsy-Porpington.

Cat

Invented by Fred and George Weasley, this was "accidentally" dropped by Fred in the Dursley's house to test on Dudley.

This knight temporarily took up residence as the Guardian to Gryffindor Tower.

Albus Dumbledore's father

The creation of Voldemort's first horcrux, the diary.

Lynx

This character was found holding Harry's wand after the Dark Mark appeared at the Quidditch World Cup.

Harry and Hermione fly Buckbeak up to this professor's office window to rescue Sirius Black.

Voldemort's maternal uncle

The birth of Albus Severus Potter.

Hare

Harry Potter purchased this magical object at the Quidditch World Cup. It can be used to slow down and replay action.

This wizard is the executioner for the Committee for the Disposal of Dangerous Creatures.

Neville Longbottom's paternal grandmother

The International Statute of Secrecy is fully put into effect.

Weasel

The village where Tom Riddle, Sr. is buried.