"Boy!" his Aunt Petunia yells, banging on the door of his cupboard. 

"Yes, Aunt Petunia." Bruce checks the cupboard door for spiders, opens it, and rolls off his mattress to stand up in the doorway, bumping his elbow on the way out. He's mostly elbows, at least the parts of him that aren't knees, but it's hard to be sure under the oversized hand-me-downs. Now, what does his aunt want? Probably for him to cook something, given the time of day, though given that it's Dudley's birthday it could be something unusual instead.

She wants him to cook this here bacon while she fusses over his cousin. 

Yup, he'll cook that there bacon. If she fusses intensely enough he can even break a bit off the end of this piece and a bit off the end of that piece and eat them without her noticing. They're hot enough to burn so he just swallows them with the minimum possible amount of tongue involvement.

She fusses pretty intensely at Dudley, who throws a tantrum at receiving one less present than last year and is placated by Vernon promising him two more. 

...It transpires that Mrs. Figg, Bruce's usual babysitter, has tripped over one of her many cats and broken something. And the backup is on vacation. 

Gosh. Poor Mrs. Figg. For that matter, poor cat. Maybe they'll take him to the zoo and leave him in the car and he'll get to explore a parking lot. Maybe he can get one more bit of bacon while they figure it out . . . Nah, better not risk it, they keep shooting him glances.

Eventually it is decided that they have no choice to bring him along. And not leave him alone in the car, that's a nice car, they can't trust him with it. Dudley attempts to throw a tantrum over this but is interrupted by the arrival of a friend he wants to look cool in front of. 

Oh wow Bruce is gonna go to the zoo! That's super great. He doesn't let how super great it is show on his face in case they change their minds. He says "Yes, Uncle Vernon" in his most neutral voice, the one that suggests he isn't going to do anything whatsoever and in fact probably doesn't exist and should just be ignored.

(Dudley's desire to look cool is not one that can be solved by his parents handing him something, and thus will have to go unfulfilled. Hopefully Dudley will not notice this.)

Piers Polkiss is as much of an asshat as Dudley and does not seem to notice how uncool the latter is. 

The zoo is great. The ice-cream lady asks him what he wants before Aunt Petunia can shuffle him away. 

Eep. "I-I'd like a strawberry bar? If that's alright?"

She gives him one with a smile, and Aunt Petunia pays for it with a minimum of grumbling. 

Later, Dudley kicks up a fuss about there not being enough ice cream in his Knickerbocker Glory, so Aunt Petunia gets him a new one. Bruce is allowed to finish the first. 

Holy cow, double ice cream! And the zoo is full of neat animals! Dudley's birthday is turning out way better for him than his own ever does, which means Dudley has actually done something nice for him by proxy. If Dudley notices this fact he'll definitely take it out on Bruce later, but Bruce is a pretty good runner and Dudley usually can't catch him until he's too worn out for effective violence. Piers is faster, though, so Bruce is going to be extra watchful until he goes home.

And now for the reptile house. 

Dudley attempts to bother a snake. The snake, unlike Bruce, does not have to live in the same house as Dudley and does not have to acknowledge that he exists. 

Wow, reptiles! Actually he's pretty sure some of them are amphibians. He reads all the little explanatory plaques and determines that yes, reptile house is a bit of a misnomer but all the species are clearly labeled.

That snake looks as zoned out as Bruce usually feels. He wanders over to it once Dudley isn't looking. "I bet you don't like being cooped up in there, do you?" he murmurs.

The snake raises its head to look at Bruce, then gives a soft side-to-side flick of its head. 

"Did that snake just understand me" collides with "is someone voluntarily having a conversation with me" and Bruce runs out of brain to be surprised with. He ends up saying, "That's too bad. I hope they at least feed you plenty. They ought to, you're useful."

The snake nods. 

"That's good. Still, I bet you'd rather be in . . . " he checks the explanatory plaque, "Brazil or somewhere." Sure, apparently the snake was born in the zoo, but Bruce doesn't remember anything before the Dursleys and still knows enough to wish things were different.

The snake nods again. 

Bruce leans against the glass, contemplating the unfairness of this situation--then jumps back in startlement as the glass disappears and ends up in a heap on the floor.

The snake looks up at him, hisses "Thanks," and slithers off, to a chorus of screams from other zoo-goers. 

This is not actually the weirdest thing Bruce has ever experienced. It is, however, the weirdest thing he has experienced recently enough that he hasn't started doubting his memory of it yet. It takes him a minute to remember that he needs to get somewhere else in the exhibit pronto so nobody realizes this was his fault. No siree, he had nothing to do with this, he was just standing here looking at the chameleon the whole time. 

His Aunt Petunia and Uncle Vernon Are Not Buying It. Of course, so as to avoid any association with abnormality, they refrain from expressing this in front of Piers or anyone else, but once they get home, he's confined to his cupboard for a while. 

Yeah, he figured. It was worth a shot though. Time to lie in bed in his cupboard and calculate the squares and cubes of increasingly large numbers until he falls asleep from hunger and/or boredom, then wake up and repeat.

Eventually, summer rolls around. Eventually, they let him out. 

Summer is the best time of year. Avoiding Dudley and his gang is easy if he can finish his chores before Dudley wakes up at noon, since they all avoid the public library the way demons would avoid churchyards if demons existed. The only hard part is getting home when it's time to cook dinner, since if they spot him on open ground they're nearly always faster. Also this summer Dudley has a stick, because apparently the school he's going to this fall requires them. Bruce is going to a different school for once, with a worse reputation but hopefully less melee combat and definitely no Dudley.

One bright sunny morning, the mail comes, as usual. Vernon tells Dudley to get it, Dudley whines for him to make Bruce do it, and Vernon obliges. 

Bruce isn't sure whether to give Uncle Vernon credit for trying to get Dudley to do something, or think he's stupid for not predicting the inevitable whining and just having Bruce get it straight off. He ponders this mystery while going and getting the mail.

Junk, junk, bill, postcard, someone wrote him a letter what the hell, bill. The letter with his name on it gets hastily folded in quarters and shoved down his too-large sock, and he brings the rest back to Uncle Vernon while trying to look even more ignorable than usual.

Uncle Vernon collects the rest of the mail from Bruce and, conveniently, ignores him. 

Being ignored: it's pretty great. Bruce does the washing-up and then takes the first opportunity to shut himself in his cupboard and check his mail. He has to hold the letter up to the crack between the door and the wall to make out the words, but it does still say "Bruce Potter, the cupboard under the stairs, Number Four, Privet Drive, Little Whinging, Surrey". In green ink, for some reason, and on oddly thick paper.

It turns out to contain the following:

Hogwarts School of Witchcraft and Wizardry

Headmaster: Albus Dumbledore (Order of Merlin, First Class, Grand Sorc., Chf. Warlock, Supreme Mugwump, International Confed. of Wizards)

Dear Bruce Potter,

We are pleased to inform you that you have been accepted at Hogwarts School of Witchcraft and Wizardry. Please find enclosed a list of all necessary books and equipment. Term begins on September 1. We await your owl by no later than July 31.

Yours sincerely,

Minerva McGonagall Deputy Headmistress

What on Earth? Okay, first of all, magic isn't real, so this is clearly an attempt to mess with him. Major points for creativity, at least relative to Dudley's attempts to mess with him, but that just raises the question of who did it and why. The key is probably that bit with "we await your owl". He doesn't have an owl and has no way of providing one to whoever sent the letter even if he did. Presumably they know that (they know where he sleeps) and are looking for an excuse to punish him for failing. Possibly they just want him to believe there really is a magic school and feel bad about missing out on it, but this letter seems like a lot of effort for someone to go to just for that.

Honestly, it seems like too much effort for anyone to put into messing with Bruce, full stop. Maybe whoever sent it is getting something else out of this too. His aunt and uncle are definitely the main suspects; nobody outside the house knows where he sleeps unless he mentioned it to Mrs. Figg at some point. In which case, they'll already know he has it and be expecting some sort of reaction. Maybe if he doesn't react, they'll think he might not have read it and do something revealing.

Bruce reads the enclosed book list, concludes that this is definitely some sort of made-up prank, and stuffs the letter under his mattress.

The next day, the only mail is another, identical letter. 

Well. That suggests his nonresponse to the first one was unexpected or unsatisfactory; on the other hand it means the sender doesn't give up easily. And it's got to be his relatives because postal turnaround time is such that nobody else could have known to send another one fast enough. Under the mattress with it.

The nest day there are six letters.

Whaaaat.

What happens if he just. Picks them up and delivers them to Uncle Vernon as if he hadn't noticed his name on them? Maybe he'll do something informative before or after the inevitable something unpleasant.

Vernon glances at them, turns away to sip his coffee, then sputters and double-takes and starts turning purple as he stares at the letters. He violently tears all six of them to shreds and then returns to his breakfast, pretending unconvincingly that nothing happened. 

Woah. Okay, pretending that didn't happen, yes. So clearly Uncle Vernon either didn't send them or is doing a really good impression of not wanting him to read them. He belatedly realizes he should have kept one of the six to see if it was exactly the same as the first.

If Uncle Vernon didn't do it, there's still a slight chance Aunt Petunia did, but it seems very weird for them to be at odds over something like this, and the former clearly knows something he doesn't. Maybe if he listens at doors for the rest of the day Uncle Vernon will say something about the letters to Aunt Petunia.