The latter part of their summer with the Dursleys, was not nearly so benign as the earlier part had been. If she had known that their summer was going to be so unpleasant, she would have enjoyed the first part which despite its monotony and general loneliness had been ameliorated quite a bit by Cho's visit. Addie's visits to the library with Harry tagging along continued, and she decided to give Cho's recommendation a try. To her delight, while the character of Mildred was perhaps too relatable to give her comfort, the essence of the book filled her with the same warm feeling that she had felt during her time at Hogwarts – one of calm and happiness – and any feelings of lingering offence swiftly departed during her second and third rereads.

The first omen that something difficult might happen was when the doorbell rang, and upon answering it, Aunt Petunia had discovered that their unsolicited visitor was Mrs Figg who lived near them. Addie, who had been peeling potatoes in the kitchen and Harry who had been dusting the photographs of Dudley had surreptitiously leaned out their heads as far as possible so as to avoid being noticed.

"Oh hello Mrs Dursley, I've been asking around just in case anyone else is interested as my Morgana (you will of course remember her, she has those beautiful white boots) had a litter of eight and I've not been able to find homes for them all even though I put notices in all the papers."

"Oh I'm sure…" said Aunt Petunia starting to close the door so as to get rid of her. Mrs Figg stopped the door with her foot.

"And while I was doing this," she said as though she had not been interrupted, "I remembered little Adelaide. Of course, Dudley has a tortoise (or should I say had), and Harry has that beautiful owl that I saw flying around so much last summer. Very unusual creature of course, but I'm glad you used to let it out so much. I heard it was unwell which I was so sorry to hear as it can be uncomfortable for them if they don't get out enough – or so I hear. And I remember that you told Mrs Elton – you know from number 15 – that they are going to that school for special children. Oh what was the name of that school again?"

"St Brutus's," Aunt Petunia answered sweetly.

"Oh yes, that was it. Well, she said that they're allowed to have pets there (for their development and recovery she said you said) and I was thinking that as Dudley had that tortoise and Harry has that owl…"

"Who is that Pet?" Uncle Vernon said, and Addie and Harry got back to work just before he came down the stairs and caught sight of them. "If it's those blasted Labour Party canvassers, tell them that I just gave generously to our local Conservative candidate. Ruddy communists. I don't want them and their… oh Mrs Figg, I didn't see you there."

"Oh Vernon, it's lovely to see you again. Now, as I was saying to Petunia, I was wondering if Adelaide would like one of my kittens so she doesn't feel left out at that school of hers. Apparently they all have something or another. A jolly good idea if I ever heard one."

"How do you know about where they go to school?" Uncle Vernon suddenly said very defensively.

"Oh, Mrs Elton mentioned that Petunia mentioned it. I didn't see it coming really. Incurably criminal children? They've always seemed to be perfectly nice to me, but I suppose that I don't see them daily."

"I suppose you don't," Aunt Petunia said, "but I really believe that it's better that they are not among the general population."

"Well I suppose that you'd know best," Mrs Figg said good naturedly. "Well, back to the kittens. Do you think that Adelaide would like one? I hear that cats are good for young people. Apparently they teach them responsibility and all that. My brother (the one who lives in the west with his wife and grandchildren just around the corner) has several and I must say that nothing has taught those children responsibility better than Rowie, Hellie and Goddie. I mentioned it to Mrs Elton when I saw her last week, yes I did…"

"Girl," Uncle Vernon yelled, and Addie very quickly noticed that this was clearly his 'company' yell. It still communicated quite a lot of his distaste in her existence, but also was unlikely to raise alarm bells for anyone else. This was his socially acceptable alternative to yelling 'brats, if you're not down here in three minutes to clean the bathroom it'll be no food for you'.

"Yes, Uncle Vernon," Addie said, after waiting for an acceptable amount of time. She wanted to give the impression to her aunt and uncle that she had been at work for the entire time, and definitely not eavesdropping, and to Mrs Figg that she had been doing something fun, like playing a computer game. She would have to remember to drop a hint about the sort of game that other children had been into when she was at primary school like SimCity or something although she had never played it. Although she could not fail to have noticed that Addie and Harry and the Dursleys did not get on very well, Addie and Harry were still encouraged to pretend that everything was fine.

"Girl, Mrs Figg is here and she is wondering if you would like one of her kittens. She says that she understands that everyone at your school has a pet."

"The presentation of the kittens," Addie breathed. She of course knew that she wasn't in fact Mildred Hubble, but there was something very exciting about something happening as if by pure coincidence.

She walked past her aunt and uncle and Mrs Figg opened the lid of the basket to reveal four tiny kittens all of whom stared up at her. Addie hadn't spent much time around cats. Maybe her parents had had one, or another pet, but the Dursleys generally thought that they were unclean, except where it concerned Dudley's tortoise, of course. She looked up at her aunt and uncle in an attempt to try and gauge their reaction. She presumed from what she knew of them from her very happy and entirely stable childhood and the conversation that she had not overheard that they would probably find something to tell her off for very soon after, but she couldn't find it in herself to care. They looked as though they were not pleased but she knew that a cat to be her own would make her very happy indeed.

"Can I choose any of them?" she asked Mrs Figg, softly.

"None of them are reserved, and I can swear as to them all being litter trained. I made sure of it myself. They are old enough now to leave their mother, and have recently been fixed so you don't have to worry about that."

Addie reached into the basket and peered down at all the adorable kittens. She knew for a fact that she was a very indecisive person, and that if she didn't choose one quickly, one would be chosen for her by Uncle Vernon so that Mrs Figg would leave. The cats all had different patterns as Mrs Figg wasn't known for her purebred cats. She regularly made it emphatically clear she thought it would be a sad existence living as a purebred cat. This wasn't quite what had happened in the Worst Witch. Addie felt a tug on her hair and looked further into the basket to see a tabby kitten, who had decided that she was Rapunzel, and she gently lifted it out of the basket and got to work with trying to detach its claws from her hair. Mrs Figg helped her, and soon both cat and child were separated, and Addie was once again free. She looked at the cat that had tried to climb her hair like a beanstalk and it looked back at her. She stroked it on the M on its tiny forehead and it looked up at her approvingly.

"I've been calling that one Gertrude, but I know that's a very old-fashioned name so you can name her anything you wish."

"Hmm," Addie said, absolutely certain that she would not be calling her kitten Gertrude of all things, "I don't really know what I could call…"

"Her," Mrs Figg said.

Addie looked up at her aunt and uncle in an attempt to get a reading on the time. Uncle Vernon was tapping his food impatiently, and Aunt Petunia looked like she was itching to get her back to work. She had to work quickly before this poor defenseless kitten got landed with a name like 'Freak', 'Disgrace' or 'Bucket'. The answer came to her suddenly via Mildred Hubble.

"Tabby," she said firmly. "I don't know much about her yet, but I certainly know that."

"That's not a proper name," Uncle Vernon protested. "You can't name a cat that! You have to name a cat Kipper or Ginger or something conventional."

"You sometimes call me girl and Harry boy," Addie said smugly. "I don't see why this is an opportunity to overcomplicate things."

"I always did like an unconventional name," Mrs Figg admitted. "I always find that cats with unconventional names end up being interesting characters. I have had cats with all sorts of names pass through my house during my time."

"I like it," Addie decided. "I think it fits her."

"I don't…" said Uncle Vernon before Aunt Petunia nudged him in the ribs to get him to stop talking.

"Why don't you take your new cat," Aunt Petunia said, "up to your room. You will be expected to look after it and feed it from your own pocket money."

"Of course," Addie said. She wasn't sure how she was going to do either of those things, but her emergency £10 note would hopefully cover most of it the next time she went to the library. Most of the holidays had already passed, and when she made it to Diagon Alley she would be able to pick up the rest of what she would need.

"Oh, I have some old things that you might like, just to save you from having to pick everything up from the pet shop. I tend to find that a community can provide most things that you need when it comes to pets. Why don't I come over again later and drop it over? It's just a few bits and pieces and most of it is in perfectly good working order."

"That would be wonderful, Mrs Figg," Addie said before Aunt Petunia could say anything about not accepting charity from their neighbours.

This is how Addie happened to become the sole custodian of a very small tabby cat with a rather unusual name as well as a litter tray, a cat carrier and a large bag of cat food, leaving her with nothing really she needed to buy for her new charge other than perhaps some cat toys. She was unsure as to how she would transport any of this to Hogwarts, but assumed that when the time came, she would be able to find a way.

As previously mentioned, Uncle Vernon was a voracious networker. He networked at work, he networked at conferences, he networked if he so happened to meet someone important in the bathroom in a public place, but most of all, his favourite way to network, was through throwing elaborate dinner parties. Aunt Petunia always enjoyed having an opportunity to put on a show, so welcomed the chance whenever it was necessary. For the first time ever, she was making a cake on the day of her niece and nephew's birthday. Of course, it was not for their birthday. It was in aid of the campaign of flattery of Mr and Mrs Mason. The only birthday cake they had received in their memory had been from Hagrid.

Addie was fully prepared to spend the day of her birthday in very much the same manner as all her previous birthdays up to this point. Afternoon nothing, evening nothing. Perhaps a nibble of the birthday muffin sent by Jen via Cho which she was trying to make last as long as she could. That would be all that marked this day as being any different from any other day. It would be no better or worse than any other birthday she had ever had before (excepting the last one of course) and she would be fine with that. The Dursleys continued to confirm their game plan. A major component of this was more lying about subjects that Dudley had written an essay on. When they talked it all over, and Addie and Harry both agreed that they would stay in their room and pretend that they didn't exist she wondered whether they were all aware of how ridiculous they were. She also found herself hoping more than anything that Mr Mason would be so floored by the Dursleys' voluntary lie that Dudley had written an essay on him that he would dig deeper and Dudley and Aunt Petunia would have to try to salvage something from the inevitable mess.

She and Harry were ordered to stay out of the way of their aunt who was cleaning, so they went their separate ways: Addie to their room to read about The Industrial Revolution with Tabby by her side, and Harry to the garden so he could mope about his friends having not sent him any letters for the entire summer. Addie didn't have the greatest impression of Ron and Hermione who both seemed to hold her in incredibly low regard, but she didn't think that they would slight Harry in this way. They had not even exceeded her lowest expectations. Part of her wanted to say "Look. This is what happens when you abandon your twin sister – your only family – to make friends with the first people you meet," but thinking about this further, she realised that this was just her being petty. There was not the slightest relation between the two. Her expectation before she went to Hogwarts had been that they would each make their own friends, but remain close. It wouldn't be particularly difficult. Plenty of siblings spent time together at school. She had heard that the Hogwarts Weasleys (as well as Harry, although she was trying not to be bitter about the fact that he hadn't even sent her a present, especially as she had sent him a book on the development of Quidditch over time that she thought he might find interesting) had spent Christmas day together, and even wore special Christmas jumpers that their mother had sent them. She had spent Christmas alone. Her first Christmas ever with a full stomach and enough money to buy herself anything she wanted, but also her loneliest.

Her only gift had come from a mysterious benefactor. It had been what was described as "The Magical Answer to the Electronic Typewriter" and printed onto both paper and parchment and had spelled in spellcheck. It used ink that one would buy if going to use a quill, and was therefore extremely easy to find the materials for. She had asked Professor Sprout, who had asked Professor Dumbledore, who had asked other members of staff whether she could use it in class and when submitting essays, and they had all enthusiastically agreed. She had tried a quill with one of the pen grips that Aunt Petunia had given her, however, she had quickly come to realise that she didn't hold any writing implement of any type at all, the right way, so even the best writing grip or handwriting support quills couldn't help her. Even Professor Snape, who prided himself in being able to read any handwriting no matter the clarity "you pathetic simpletons" (Hogwarts staff room c.1991) agreed on the basis that Adelaide Potter's handwriting was the worst that the school had ever seen.

Making sure that she didn't give away the game on her dislike of his friends and her rather unfortunate glee about him having to deal with not having anyone to talk to for once, was a fairly simple feat as no matter what she felt, her facial expression always was that of a moderately depressed Basset Hound. When she had been pressured into joining her primary school choir, a teacher had been awful to her about not smiling. At the time she had been having a wonderful time and the teacher by saying this had unwittingly ruined her day. She ended up not returning which had been a shame. Harry would have no idea about how she truly felt. He looked like she assumed everyone thought she did.

Some time later, Harry came upstairs from where he had been sulking in the garden. The Masons were due to arrive soon and neither of them wanted to upset the order of things. She heard him stop dead upon entering the room, and she became unwillingly acquainted with the concept of a house elf.

Later, when they were each lying on their separate beds while they listened to Uncle Vernon trying to stay on top of a ladder while he installed bars in their window, Addie pulled Tabby into her lap and thanked Merlin that whatever was in the litter tray that Mrs Figg had given her didn't smell at all. She doubted that even magic could have done it better. Harry had barely even complained that they now had to share a small room with a cat and an owl. Addie felt that it was entirely fair enough for her to have a cat if he had an owl.

"Harry," she said, "did that erm 'house elf' really levitate the pudding?"

There was a sound from the other side of the screen as though Harry was clearing his throat. After a moment he replied.

"Yes," he said.

"Ok," she said.

She believed him. She supposed that she was the person most likely to believe that he hadn't done anything wrong, as a direct result of their shared childhood. She had been the only one who had believed him when he had said that he had not been the one who had turned their teacher's wig a different colour, and he had been the only one who believed her when she had said that she hadn't been the one to make the fire alarm go off before they started their first and only swimming lesson. Of course it was now evident that they had both been responsible for what had happened, but in the moment, it had been nice to have a person in the world who believed that you had not done anything wrong. Neither of them had had anyone else, and in a world where magic clearly didn't exist it was now nice to know that there was an explanation.

She rolled over to face the wall and put in her earplugs in an attempt to block out the loud discussion coming from downstairs. Clearly Uncle Vernon and Aunt Petunia weren't sure what to do with them. She tried to get to sleep, but her thoughts were unable to move away from the tearstained face of Dobby punishing himself. She of course had known the magical aristocracy had people like Neville's enemy – Malfoy – and his family had some questionable ties, but she hadn't realised that slavery was so commonplace she hadn't even been told about it. The history books she had read outside of schoolwork had been full of accounts of human-creature cooperation and the slow movement towards employment rights and safer workplaces throughout the magical world, but nothing of this.