I imagined those jaws ripping, chewing, swallowing. I shuddered. 'How do you feed them? You don't get in the tank with them, do you?'

'No. We feed the conger eels in the tank, but not the sharks.'

'You'd end up as food yourself,' I said.

'No, not these babies. We do swim among them sometimes but not when the public's around.'

'You don't!' I didn't know if he was kidding me or not.

'Yes we do,' he said. He reached into his pocket and pulled out something white and pointed. 'Shark's tooth!' he said. Then he held out his hand. 'Go on, you can have it, seeing as you're so interested.'

'Really?' My hand closed round the tooth before he could change his mind.

'They're meant to bring you luck.'

'Thank you so much,' I whispered, clenching the tooth tightly in the palm of my hand.

The attendant walked off with a nod and a wink.

'What did that man give you?' Kendall asked.

'Oh, just a peppermint,' I said quickly. I put my hand up and pretended to eat it. 'You don't like peppermint, do you?'

'I like Kendal mint cake,' said Kendall.

'I do too,' I said. 'Come on, we'll buy you an ice cream because you've been so good.'

I kept the shark's tooth hidden in my hand all the way home. I felt mean because I knew Kendall would be thrilled if he knew about it, but he'd want it for himself. I had to keep it safe until I could give it to Mum.

I was sure it was a lucky talisman, able to work magic and make Mum better. I'd endured the hour-long torture of the shark tank. This was a sign that I had completed my task. I had shown the Voice of Doom.

Mum was going to get better.

Auntie Barbara was out when we got back, obviously at the hospital. I wished we'd stayed up in London. It was a long, long afternoon. Then Auntie Barbara came back at last. I heard her hurrying up the stairs. When she burst through the front door she could barely speak she was so out of breath. Her hair was tumbling out of her ponytail and there were damp patches on her blue shirt.

'Where have you been?' she gasped. 'I went to the school to pick you up and you weren't there. Ms Balsam said you hadn't been at school at all today. How could you do this to me, Lola Rose at a time like this?'

'I'm sorry. I I had to go to the aquarium. I didn't want to worry you. I left a note.

'Don't you dare do that ever again!' said Auntie Barbara. 'You went to the aquarium? For goodness' sake, hasn't Kendall been there enough times already?'

'It wasn't for Kendall. It was for me. To make Mum better,' I said. 'She is better, isn't she, Auntie Barbara?'

I held the shark tooth so that it dug into my palm. Auntie Barbara looked at me. She was struggling. Then tears started splashing down her flushed face.

'No, she's worse,' she said, starting to sob. 'They can't get her temperature down. The antibiotics don't seem to be working. That's why I came to collect you. You're not allowed to see Mum but I thought you could call to her from the corridor.'

'She's dying, isn't she?' said Kendall.

'No!' I said.

'Maybe she might be dying, Lola Rose,' said Auntie Barbara. She put her arm round my shoulder.

'She can't be! I made her better! I stood right next to the sharks. They swam right up close, but I didn't run away. I've got the magic tooth. She can't be dying!' I sobbed. 'What did I do wrong? Should I have stayed longer? What?'

'Stop it, Lola Rose. You haven't done anything wrong. You haven't made Mum ill and you can't make her better, no matter what you do.'

'I can. I've tried so hard. I've got the lucky shark's tooth, look!'

'Let me see! Where did you get it? I want it,' Kendall cried, trying to snatch it.

'It's Mum's,' I said, holding it high above his head.

'Then we'll go and give it to her,' said Auntie Barbara. 'But it's a present, Lola Rose. It's not magic. It can't make her better.'

'It can!'

'Well . . . we can give it a go,' said Auntie Barbara. 'I'm going to have the quickest wash and change ever, kids, OK? Ready in five minutes.'

I decided to change too. I put on my best black top and purple velvet skirt. It was too hot for a furry jacket but I wore it anyway. I dressed Kendall in his black leather jacket although he complained. And he went on and on about the shark's tooth.

'I keep telling you, Kendall, it's for Mum. But when we go back to the aquarium I'll ask for one for you.'

'Not when you're meant to be at school,' said Auntie Barbara, bright pink from her quick bath. She wore her purple Thai silk two-piece edged with silver braid and her silver flip-flop sandals.

'You look lovely, Auntie Barbara.'

'Thank you, Lola Rose. So do you. And you too, Kendall. OK, have you got your shark's tooth? Right then, darlings. Off we go.'

We met Andy and Steve coming up the stairs.

'You look like you're going to a party,' said Steve.

The Voice of Doom bellowed through the banisters. A farewell party. I clutched my shark's tooth so hard all the way to the hospital that it scored a deep red scratch on my palm.

'It's bitten you,' said Kendall.

We trailed along endless polished corridors. Kendall's sandals squeaked, my heels tapped and Auntie Barbara's flip-flops slapped at every step. When we got to Mum's ward Auntie Barbara made us wait while she went into the side room where they were now nursing her.

We waited a long time. I took Kendall's hand.

'That's not the shark's-tooth hand, is it? I don't want it to bite me too.'

'It's in my other hand. It's OK.'

'It isn't OK, is it, Lola Rose?' Kendall said, weaving his fingers into mine. 'What have they done with our mum? Why won't they let us go and see her?'

'We might be too germy. But Auntie Barbara says we can call to her. Shall we try calling now?'

'What will we say?'

'Anything. Stuff like "We love you, Mum. Get better soon."'

'I shall feel silly, calling out,' said Kendall. 'All these ill people will stare at us.'

'We'll go right up close, by the door. Come on.'

We walked to the door of Mum's side room. It was half open. I peeped round fearfully. Mum was there in the bed, but she had a mask over her face and tubes running in and out of her. I could only be sure she was Mum because of the blonde hair tumbled on her pillow. A nurse was taking her temperature and arguing with Auntie Barbara.

'It's more than my life's worth to let the kids in, you know that,' she said.

'What does it matter now?' said Auntie Barbara. 'Think of the children. They need to see their mum. And it could just help her. She loves those kids so.'

'I think she's out of it already,' said the nurse.

I started crying and the nurse looked up. She saw me and then nodded.

'OK. Quick. Come and see your mum for two minutes. But I'm scooting out of here, right?'

Kendall and I tiptoed towards the bed. Auntie Barbara carefully threaded her arm through all Mum's tubes and stroked her clenched fist.

'Nikki, sweetheart, the kids are here. Jayni and Kenny. Lola Rose and Kendall. They've come to say hello.'

Mum's eyes stayed shut. Her hand didn't unclench.

'Mum?' I said. 'Can you hear me, Mum? Listen, I want you to have this.' I reached for her clenched hand and gently prised her fingers open. I squeezed the shark's tooth inside. 'There! You'll never guess what it is, Mum. It's a shark's tooth, a real one. It's really really lucky. I did this hour-long ordeal and it was my reward. It's going to make you better.'

Mum didn't stir.

'I haven't got a shark's tooth to give you but you can have a whole shark if you want,' said Kendall. He thrust grubby George under Mum's arm.

'Did you hear that, Mum? Kendall's given you George,' I said.

'Not for ever and ever,' Kendall said. 'It's just a borrow.'

'But you can keep the shark's tooth. When you're better we could bore a hole in it and hang it on a piece of string round your neck.'

'I'm not wearing a tacky bit of string,' Mum mumbled, making us all jump. She opened her eyes.

'You're still alive, Mum!' I sobbed.

'Of course I am. And I'm going to get better. I've got to look after you two, haven't I? Now clear off, kids. I've got a lousy headache and you're doing my head in.'

We kissed her burning forehead, Auntie Barbara, then Kendall, then me. I took George back because I knew Kendall wouldn't be able to sleep without him and George was a total germtrap too.

'I've made you better, haven't I, Mum?' I whispered.

'I've made me better,' said Mum. 'I can do anything. I'm Lady Luck, aren't I?'

Mum's fever went down, but she had to stay in hospital a while. Then she was well enough to come home, though she still had to go for her treatment. First the chemotherapy, weeks of it.

All Mum's beautiful long blonde hair started falling out after the second treatment. It was so scary at first. Kendall and I were cuddled up with her in bed in the morning and when she sat up great long locks of her hair stayed on her pillow.

'Oh my God,' Mum gasped. She put her hands to her head, feeling the bald patches. 'This is just like being in a bloody horror movie!'

'Never mind, Mum. It's only a few curls,' I lied.

Mum's fingers ran along her scalp, feeling. More hair fell out there and then, fluttering down over her nightie in long pale strands. Mum started whimpering, hanging onto her head with both hands as if she were trying to keep the rest of her hair in place.

Kendall started crying too, his eyes screwed up so he couldn't see Mum properly.

'What's up now?' said Auntie Barbara, sailing into the room in the great black silky caftan she wore as a nightie.

'Look!' Mum wailed.

'Oh God, your hair, you poor love,' said Auntie Barbara. 'Right. I know what we can do. Lola Rose, you've got a pair of sharp scissors, haven't you?'

'It's cut-my-throat time, right?' Mum sniffed.

'I'm going to cut your hair, Nik.'

'No! I've always had long hair. It's part of me.'

'Not any more, darling,' said Auntie Barbara sadly. 'Come on, sit on the chair, and we'll get snipping. It'll be less strain on the roots if it's very short. Maybe we'll be able to keep some of it that way.'

Auntie Barbara cut Mum's hair really short. I gathered up all the locks and twisted them into a big soft plait and tied it up with purple ribbon.

'You can pin it back on, Mum,' I said.

'It's not going to work. I look awful. Like a skinhead,' said Mum, crying.

'No, you know who you do look like, Mum?' I said, staring at her ruffled short hair and pale face on her little stalk neck. 'Kendall!'

'Great!' said Mum. But then she wiped her eyes and stuck out her bottom lip and lisped, 'I want George!' Her Kendall imitation was spot on and we all laughed.

Cutting her hair so short didn't really work. It all fell out anyway until poor Mum was completely bald. Her head looked horribly naked. The hospital gave her a wig but it didn't look right and Mum said it itched like crazy. She cut up some of Auntie Barbara's Thai silk into scarves and wound them round and round her head, and then she pinned the plait I'd made her at the back.

'That looks ever so pretty, Mum!' I said.

'Pretty frightful,' said Mum, peering into the mirror and sighing. She puffed out her cheeks. 'And I'm not just an old baldy-bonce. I'm getting fat.'

I always thought you got thin when you got cancer. Mum really was getting fatter. The chemotherapy drugs gave her a big round face and a big round body too.

'Yuck! Look at me,' she said, struggling to pull her zip up over her stomach. 'I'm going to have to buy some new jeans. New everything.' Even her lovely white jacket was too tight for her. 'You'd better have it, Lola Rose,' she said.

'It's yours, Mum. You'll get thin again when you're better.'

'I don't think I'm ever going to get better. And what's the bloody point if I end up looking like a freak? I can't stick being so fat!'