I'm trying to reread years 1 through 6 before year 7 comes out. I'm about half way through year 2 and I've noticed a couple of interesting things:
Everything used by Malfoy to try and kill Dumbledore in year 6 shows up in year 2. When Harry accidentally ends up in Borgin & Burkes, he hides in the vanishing cabinet (although it's not named as a vanishing cabinet and he doesn't close the door all the way). The necklace is spotted and it is mentioned that its cursed and has killed its last 19 muggle owners. The candle that only give light to its holder also shows up. I'm pretty sure those are the only items that get described during the visit. And later, when Harry is in Filch's office, Peeves breaks the Hogwarts vanishing cabinet. It is identified as such.
Interestingly enough, Year 2 takes place in either 1992 or 1993; which we know because Harry, Ron, and Hermione attend the 500th anniversary of Sir Nick's deathday. The party takes place on Halloween and the cake states that he died in October of either 1492 or 1493). I'm fairly certain this is the only time you find out exactly when the Harry Potter books take place. I think this is noteworthy because the book is copyrighted 1999. Why was this date chosen? No clue.
Finally, I notice that Deadalus Diggle comes up a lot. He's the first wizard who's full name you hear in year 1. And he shows up two other times before Harry makes it into Diagon Alley for the first time.
Some wild theories:
Mrs. Weasley dies in year 7. I've been claiming this one for a while, but now I'm willing to bet on it. Why?
* She's the only mother figure for Harry.
* Harry has already lost 2 father figures.
* She always worries about everyone else.
* And there's dramatic necessity. A Weasley is always placed in peril. (Year 1: Ron with the giant Wizard's chess set; Year 2: Ginny in the Chamber of Secrets; Year 3: Ron abducted by Sirius; Year 4: Ron at the bottom of the lake; Year 5: Mr. Weasley in the Ministry of Magic; Year 6: Ron with the poisoned mead and Bill during the battle at Hogwarts.) It's become such a common occurrence that there's no suspense left when one of them is in trouble. To make year 7 dangerous, it makes sense to put a Weasley in danger early on and then kill them--just so J.K. can let readers know that she isn't fracking around.
I go with Mrs. Weasley instead of Ron because you just can't kill Ron at the start of year 7 and I think this death needs to come early on in order to make the rest of the book feel dangerous. Everyone knows a big death is coming; most people expect it won't come until the end. Kill someone early and the stakes have been upped for everything that comes afterward.
3 hours ago