Someone had scribbled all across the top of the paper in bright orange highlighter: UR DAD IS SICK SICK SICK.

When I didn't go back to class, my teacher sent a girl called Liz to find me. Liz was the kind of girl who always has a sharpened pencil and gets to be class leader because she is so responsible. She found me blubbing in the girls' toilets, but I refused to say why.

'Come on,' she said kindly, and put her arm around my shoulder. 'We're just about to have a story. You don't want to miss that.'

The next day, there was a note in my school bag. Another article, from another website. And the day after that. It went on for months. Sometimes it was in my bag, sometimes in my desk, sometimes in my coat pocket or my violin case. There were articles about the court hearings, and about Dad pleading guilty to manslaughter, and about him getting six years; and always a message in the orange highlighter.

I dreaded going to school.

One day, I nipped out of the classroom to get my violin. Liz was standing with her hand in my coat pocket. She looked at me. I looked at her.

'Hi, Scarlet!' she sang, cool as a cucumber. 'Looking for my wallet. Someone's swiped it. Mum said to check all the pockets.' Then she turned around and walked away, with a piece of paper in one hand and her long hair swinging. I never got any more notes after that.

People aren't always nice, I can tell you that for free.

So that's why I made friends with Vienna, and only Vienna, though to be honest I probably wouldn't have chosen her as a friend if my mum hadn't died. She's not the sharpest knife in the box, but what you see is what you get. There's no way she'd have bitched behind my back or left horrible notes in my bag. She has mousy-brown hair which she wears in a fountain ponytail, and a freckly face. She eats too much chocolate and I'm afraid it's starting to show on her bum. She lives with her mother and stepdad on an estate near the ring road, and she has a TV and an Xbox 360 and a computer in her bedroom. Oh-and an ensuite and a king-sized bed with a pretend fur cover, like something off a James Bond film.

Hannah disapproves. I once heard her say that Vienna's parents are 'criminally negligent of that child's intellect, such as it is'. Hannah thinks young people shouldn't be encouraged to live in a virtual world, because the real world is jam-packed with magic. According to her, there are whole universes in a single atom. She's published papers about that kind of thing.

I often go to Vienna's house after school. We let ourselves in with a key they keep hidden in the garden wall. We tell our families it's to do homework together, but actually we Facebook and watch TV. I was there just before the Christmas holidays began. We were watching The Vampire Diaries, lazing on the James Bond bed.

'My dad's taking my grandparents to court,' I blurted.

'Bunty did that,' Vienna replied casually, eyes glued to the TV screen. Somebody was about to get their blood sucked. 'Mum's boss. Sued the council because she slipped on a pavement.'

I didn't care about this woman Bunty, who really should have looked where she was going 'My dad wants to see us,' I said.

'Is he out, then?'

'Yep. He only had to do half his sentence. Some stupid judge might make us go and see him. If that happens, I'm running away.'

Vienna turned the TV down. This was more interesting even than a blood-sucking. 'They can't make you-he's a murderer!'

'I know he's a murderer.'

'Are you scared?'

I thought about just how scared I was. Ever since I'd seen that man outside my school, something had been living in my stomach. It seemed to have tentacles that spread all through me. 'Nah,' I said.

'I'd be sooo scared.'

'Well, I'm not. If I get the chance I'll tell him to sod off, and good riddance to bad rubbish.' As soon as those words were out of my mouth I felt even worse. I burst into tears.

Vienna is a good friend, really. She grabbed the remote and turned the TV off. Then she sat there looking awkward and muttering 'cheer up' while she patted my back.

'It won't be much of a Christmas with this hanging over us,' I wailed. 'Why can't he leave us alone?'

'I know what you need!' cried Vienna. She dashed over to her fridge (yes, she actually has a fridge in her room) and dug out a bar of Caramello. She believes everything can be cured by chocolate. Actually, it wasn't a bad idea. I had to stop blubbing so that I could eat it.

'What's your dad like?' she asked, once I'd calmed down. 'Do you remember much about him?'

I did. I did. I didn't. I had about a million memories, all swirling around in tiny pieces in my head like a cloud of ashes above a bonfire. I had pictures and sounds and feelings. The soapy smell of him; a greeny-blue jersey; his voice with the soft accent; the fun of being high up above the world when I rode on his shoulders, strong hands holding on to my shins to stop me from toppling off. I had feelings of total adoration and also of being so scared I wet myself.

'Not really,' I fibbed.

'You were ten, weren't you? I can remember loads of things from when I was ten.'

'I remember him punching my mum,' I said.

'You mustn't ever forget her.'

I lay back on the pretend fur cover and looked up at the ceiling. I had this fear that I was already forgetting Mum. It was as though she was standing on a boat, sailing away. I could still see her waving, but her face was blurred.

'Um . . . my Auntie Carolyn was over last night.' For some reason, Vienna's voice had dropped to a whisper. 'She brought her new boyfriend.'

'Really?' I wasn't remotely interested in Vienna's aunt.

'Mm. They all drank a lot of wine, and . . . well, Carolyn started talking about your mum. It turns out she knew her. They worked together in a bar next to the river.'

Now I was interested. 'What did she say?'

'She said Zoe-your mum-was fun to be around. Charismatic, she said. Loads of friends. People just couldn't get enough of her.'

'Charismatic.' I shut my eyes, feeling much happier.

'She also . . . um . . .' Vienna stopped. I heard her scratching her leg. 'Um, no. That's all, really.'

I opened my eyes again. 'She also what?'

'Nothing.'

'Vienna!'

She stretched herself out next to me, with her head propped on her hand. 'The truth is, I don't think Carolyn got on with your mum. She said some things that weren't so nice.'

'Like what?'

'Not very kind things.'

'Yeah? Like what?'

'I just don't think they got on. Don't worry about it. Forget I said anything.'

I sat up. 'It's too late to be tactful. The cat's out of the bag.'

'You'll be angry.'

'I won't.'

'Promise you won't shout?'

'I promise.'

'Okay.' She was biting her lower lip. 'Auntie Carolyn said that underneath all the razzle-dazzle your mum was actually a total bitch who always had to be the centre of attention. Erm, she said most people didn't get that, especially men. She slept with the customers-with "anything in trousers". Carolyn said she went nuts in the end and started smashing glasses. They had to call the police. The last she heard, your mum was in the bin.'

'The what?'

'The bin. And she read in the papers that your mum was totally rat-arsed the night she died, which was probably why a couple of punches killed her. If she'd been sober, she mightn't have died. It's something to do with the brain.'

I'd promised, but I was furious. I felt like screaming at the top of my voice, spitting and swearing and tearing up that stupid fur cover.

'It sounds as though it's your Auntie Carolyn who's the complete bitch,' I snapped, jumping off the bed.

Vienna's face crumpled. 'You promised,' she sobbed. 'I knew you'd do this.'

I had promised; and I knew it wasn't Vienna's fault her aunt was a slithery, fork-tongued snake in the grass. All the same, I wanted to hurt somebody. So I dug the fingernails of one hand into the back of my other wrist until I felt one of the nails go through the skin. It really hurt. It made my eyes water, and I felt sick.

'Didn't you stick up for my mum?' I shouted.

Vienna wasn't really crying. She was hamming it up. 'They didn't even realise I was listening. I was playing Minecraft in the living room with my headphones on. I just stared at the screen with my mouth hanging open. Adults think you can't hear them when you do that.'

I sat down again. 'What did she mean by "in the bin"?'

'Prison, maybe? You know, sin bin.'

'Anything in trousers?' It sounded so ugly.

Vienna covered up her legs with the fake fur. 'She did admit that your mum was beautiful . . . no, that wasn't the word . . . attractive. She said, "Zoe was certainly attractive, can't be denied. Just like a Venus flytrap".'

'A Venus flytrap? That's horrible! They eat the flies alive.'

'Sorry. It's just what she said.'

I took a minute to think about all this. 'Sounds like your aunt's a small, mean person and she was jealous of Mum.'

'My stepdad can't stand her,' agreed Vienna. 'Even though she's his sister. When she rang to say she was coming round, he slammed down the phone and said to my mum, 'Christ almighty, Val! Hide me! Motormouth's on her way over.''

'So did he hide?'

'Mum wouldn't let him. She said he could entertain his own flipping family, they're all morons and she married him, not the whole flipping tribe.'

We shared another bar of chocolate while Vienna listed all the things that most annoyed her about Carolyn. I probably seemed back to normal by the time I stood up to leave.

'You okay now?' Vienna eyed me uncertainly, as we waited for Gramps at the gate.

''Course I am! Gotta run-here he is.' We did hugs, and I dashed off to get into the car.

'Good day at school?' asked Gramps, once we were on the road. He was wearing his tweedy cap and leather driving gloves.

'Fine, thanks.' I was daydreaming about walking up to Auntie Carolyn and smacking her right on her ugly gossipy mouth.

He wanted to chat. 'Did you have drama?'

'No.'

'Music?'

'Yes. Gramps, what does it mean if you say someone is in "the bin"?'

He slowed down for a set of traffic lights. 'Well, that depends on the context.'

'If someone's gone nuts and started throwing things, and ended up in the bin.'

'Ah. In that case, they're probably talking about a hospital for people with, um, mental health problems.'

'Oh my God! So they mean the loony bin?' I couldn't imagine my mother having anything to do with a place like that.

'Well, yes, I believe that's the expression. I don't like it much.' Gramps sounded calm, but his hands were shaking on the wheel. In fact they were shaking so badly that I wondered if it was safe for him to drive. 'You know, Scarlet, a lot of people have mental health problems at one time or another. An awful lot. A person might have an episode, and then never be troubled again their whole lives.'

'So you mean I could get ill like that?'

'You?' He actually took his eyes off the road to glance round at me. 'Why ever do you ask such a strange thing?'

'No reason. Just wondered.'

'In the bad old days,' said Gramps, 'society locked people up and threw away the key. Terrible things were done to them-and I suspect that most were as sane as you or I. Saner, probably. Nowadays we know better. Really, with a lot of these problems it's just like having a broken leg, or maybe measles. People get help and then they're quite well again.'

'I see.' I didn't see at all.

Another set of traffic lights, this time the slow ones near Bootham Bar.

'Rush hour,' grumbled Gramps. 'The sheer weight of humanity.'

I watched his fingers in the brown driving gloves, tapping the wheel. I had to ask. I just had to. I needed to hear that the answer was no. 'Mum was never ill like that, was she?'

The fingers stopped tapping.

'Gramps?' I felt panicky.

'Yes,' he said quietly. 'She was. For a time. But she got better.'

My heart began pumping too fast. The other things Carolyn had said flew screaming into my head like rockets. A total bitch . . . slept with anything in trousers . . . Venus flytrap. Perhaps they were true as well.

'Why didn't you tell me?' I asked.

'Because it isn't important.'

'Of course it's important!'