It was three days before Hermione was able to make the trip again.
But the day before she was available to meet him again she sent him a letter via Hedwig letting him know she'd be coming, so Harry wasn't left alone long enough to resort back to his moody, temperamental self that he'd been the day and a half before she'd come for her first visit. Deciding it best to avoid his aunt and uncle as much as possible, Harry returned the owl with a note telling her to meet him at the park she'd passed on the way from the train station to his house on her first visit. As hot as it'd been so far that summer, Harry knew there was little chance of them being overheard by anyone at the park, since no one would be there.
Walking through the empty, desolate park, he kicked a few dried-out weeds, when he heard someone yelling his name. Looking up, he saw that Hermione had entered the park from the other side, and was waving and yelling at him from under the only tree in the park, and the only semblance of shade in a several mile radius.
Harry had barely sat down next to her when she exclaimed almost accusingly, "You never told me you own Sleekeazy!"
"Own what?" asked Harry, completely confused — he didn't own anything, a full vault at Gringotts excluded.
"Sleekeazy's Hair Potion! When I told you after the Yule Ball last year about how all the girls in my dorm were using Sleekeazy to fix their hair up for the Ball, you never told me that you own it!"
Harry stared at her in surprise for several seconds, before answering slowly, "If I do, I certainly didn't know it. Are you sure?"
"Of course I am, Harry," admonished Hermione. "Your grandfather started the Sleekeazy Corporation in 1926, and it's still in the Potter family. Which means you now own it, since you're the only remaining Potter. Also, the Potters were already a very wealthy, very powerful wizarding family before Fleamont ever started Sleekeazy. Your parents and grandparents never lived lavishly by any accounts, which means all that money still has to be somewhere."
"How did you find all this out?" asked Harry, still staring at her in shock. He knew Hermione was a walking library, but he'd never heard anyone mention Potter in connection to Sleekeazy, and it seemed an odd bit of trivia to pick up from school books.
"After you mentioned how much money you had in your vault, it got me thinking, and I tried to do some rough calculations based on what you said of how much your vault's value probably is. So when I came to a rough estimate of fifty-thousand galleons, and possibly more than that, I got my mum to take me to Diagon Alley the next day to find some books that might explain why you'd have that much money as an eleven year old.
"That was too much money for both for a moderately well-to-do family, and an extremely well-to-do family. Had it only been twenty or thirty-thousand, then I would have said your parents were moderately well-to-do, and just left you the whole thing since it was easier than trying to split it up into different vaults. But if their entire worth was fifty-thousand, that's enough to give you ten or twenty-thousand for school, and then the remaining thirty or forty-thousand once you came of age. Now, if they were the Malfoys, it'd be one thing for them to leave you with an extravagant amount of money, but your parents seemed like they'd want to raise you to be reasonable with money — which you definitely are.
"But from what I calculated, they left you fifty-thousand or more in a vault you theoretically had access to from the moment they were murdered when you were only fifteen months old. It just didn't make any sense. And it's not like your parents' murder came as a surprise to them, and they died without ever having the chance to set their affairs in order. They knew Voldemort was after them for a substantial amount of time before their actual murders occurred, and there was a war going on since long before you were born that was constantly claiming people's lives unexpectedly. My point being, it's not like they mistakenly assumed they were going to be able to raise you your entire school years, and so hadn't prepared for their deaths and your upbringing at all, and you ended up with the entire amount all at once.
"Because estimating from my own four years of experience attending Hogwarts, removing my love of books from the equation, to make it through seven years of school, or really only six until you come of age at seventeen, you need less than a thousand galleons. So even to make sure you weren't lacking anything during school, five to ten thousand would be more than enough. So them giving you the full fifty thousand or more that's in your vault, if that was their entire worth, didn't make any sense. The interest alone over seven years should cover your schooling needs, and as a wizard you could legitimately live off of fifty thousand galleons your entire life — far less if you were a Weasley. And I'm not sure all nine of them combined will go much over that — but I'm getting off topic.
"Getting back to your vault, Sirius told you when you stopped Pettigrew and rescued him, that your parents appointed him as your guardian in case anything happened to them. And Sirius then offered to let you come live with him, which means he has a house and the resources to raise you for what would have been the next three or four years, depending on whether you count your of-age seventh year — which knowing Sirius as we do, he definitely would have included your final Hogwarts year when he invited you to go live with him. And that's all besides the fact he bought you the nicest racing broom that's ever been built as a Christmas present, which was a very pretty penny. So he can't be hurting for money, either.
"Which means it's not like your parents would have thought you'd need money to pay for somewhere to live if they died. And even if they had wanted to make sure you did have money for that just in case it was necessary, it would make more sense to have a separate vault just for that scenario — kind of like the Bribe-the-Ministry Vault I'm sure the Malfoys have and keep well-stocked. And it's not in the least bit difficult to set up a vault at Gringotts — I could even as an underage muggleborn witch if I wanted to. Because my parents actually asked about setting up a vault in Gringotts for my schooling the first time we visited the summer before my first year. They were turned down because only wizards are allowed to set up vaults, but the goblin said that I could set one up if I wanted to. They didn't decide to go that route with me, but my point being, vaults aren't that hard to set up.
"So given all of that, when I went to Diagon Alley on Tuesday with my mum, I got some books on prominent wizarding families of the nineteenth and early twentieth century to see if I could find any Potters. And the very first one I looked through proved true my suspicions that that can't be your only vault. The book was on major wizarding inventions of the past couple centuries, and your grandfather, Fleamont Potter, invented Sleekeazy hair potion — which is still a very prominent business to this day, something anyone who hangs around in girls dormitories much at all knows. It's just that the Potter name has never directly been attached to the company, so most people don't know it's the Potters', because they don't read about things like that.
"But as I continued reading through all of the rest of the books I bought, it turns out your family's actually a lot more important than they've appeared over the past couple generations. The Potters used to be a very prominent family, which in the wizarding world has always meant money. So while I can't give any guesses as to what you're actually worth, it's a whole lot more than the galleons you've got in your vault that you've had access to since first year."
As Hermione wrapped up her story, Harry simply sat there staring at her, still trying to absorb everything she'd told him. After letting him sit there like that for a minute or two, she leaned over and pecked him lightly on the lips to bring him back into reality and out of his shock.
"So...you're saying I'm wealthy beyond my dreams?" Harry asked slowly, trying to comprehend everything Hermione had just told him.
"Well, I certainly can't say for sure, Harry," answered Hermione cautiously, "but from what I've read it seems possible. Probable, even. But we should visit Gringotts to find out for sure. Also, I need to look up the creatures you saw pulling the carriages, that I didn't have time to do on Tuesday."
"I don't know how happy my relatives would be about me leaving Privet Drive, though," said Harry.
"Do you normally ever see them during the day?" asked Hermione.
When Harry shook his head, she continued on slightly mischievously, "Then I don't think a little day trip they never know about will hurt anyone. And you could definitely stand to get away from this place for a day."
So Harry and Hermione spent the rest of their day together walking the streets of Little Whinging, talking and planning their excursion to Diagon Alley and Gringotts. By the time Hermione left to catch the last train back home that evening, they had everything all planned out.