Let's recap some of the events written in the Harry Potter books during the month of April.
and Harry Potter Wiki
1992(Harry Potter and the Philosopher's Stone)
April 24 A Norwegian Ridgeback Dragon named Norbert hatched in Hagrid's hut.
1994(Harry Potter and the Prisoner of Azkaban)
April 20The Committee for the Disposal of Dangerous Creatures holds a hearing on the fate of the hippogriff Buckbeak.
1995(Harry Potter and the Goblet of Fire)
Mrs. Weasley sent a package of Easter eggs with Percy's letter enclosed to it to Harry Potter, Ron Weasley and Hermione Granger. Both Harry and Ron's were the size of dragon eggs and full of homemade toffee, while Hermione got eggs which the size is smaller than a chicken egg. Her face fell when she saw it.
1996(Harry Potter and the Order of the Phoenix)
Dumbledore's Army is discovered after Marietta Edgecombe informs Dolores Umbridge about the organisation.
Albus Dumbledore takes the fall and leaves Hogwarts School of Witchcraft and Wizardry.
The Ministry of Magic appointed Dolores Umbridge as headmistress of Hogwarts.
1997(Harry Potter and the Half-Blood Prince)
Harry Potter got the Felix Felicis from Professor Horace Slughorn, They attend Aragog's funeral along with Rubeus Hagrid. Harry successfully got the partial memory of Slughorn and view it with Prof. Dumbledore. Harry first to understand what Horcruxes is,
Lavender Brown with Ron Weasley and Ginny Weasley with Dean Thomas ended their relationship.
1998(Harry Potter and the Deathly Hallows)
The Battle of Malfoy Manor occurs after Harry Potter, Ron Weasley, and Hermione Granger are captured by Snatchers and Dobby comes to their rescue.
- Peter Pettigrew's death.
Harry Potter, Ron Weasley, Hermione Granger with Mr. Ollivander, Dean Thomas, Luna Lovegood, Goblin Griphook and injured Dobby arrived at the Shell Cottage, a place owned by the newly-wed Bill Weasley and Fleur Delacour.
- Dobby's death.