‘This is a nice car, and you go much faster than Mummy. Can I have an ice cream?’

‘May I. You may if you promise to eat your supper.’

On the way back, however, Tabitha smiled sweetly at Cameron. ‘You haven’t got a husband, have you? Why don’t you get one?’

‘I’d like to,’ said Cameron, thinking longingly of Rupert.

‘But not my Daddy,’ hissed Tabitha.

‘It is absolutely ludicrous,’ said Cameron to Rupert as, later, they listened to Tabitha sulkily crucifying Beethoven’s Minuet in G on the drawing-room baby grand. ‘This is a Saturday during the vacation and she’s got to learn her vocabulary.’

‘Helen is petrified the children will inherit my lack of brains.’

‘Marcus is clearly superbright,’ said Cameron. ‘He’s such a sweet, sensitive kid.’

‘Takes after his mother,’ snapped Rupert. ‘Tab takes after me. My reports were much worse than hers.’

‘She doesn’t strike me as being dumb,’ said Cameron, ‘just unmotivated.’

‘She looks OK,’ said Rupert coldly. ‘And she rides like a dream. What else matters?’

Supper was decidedly scratchy. Tab ostentatiously gave all her shepherd’s pie to Beaver. Afterwards Rupert packed both children off upstairs to watch James Bond. Cameron was reading the Guardian in the drawing-room and feeling absolutely shattered. How the hell did mothers cope day in and day out, when piercing screams rent the air? The next minute Marcus had run into the room, waving the remote control. He had difficulty breathing.

‘I don’t think Tab should watch this video. It’s called For Your Eyes Only, but it’s not James Bond.’

‘You got it, didn’t you?’ said Rupert unhelpfully.

A second later Tab came storming in and tried to grab the remote control. When Marcus held it above his head she went for him, kicking his shins and giving him a karate chop in the stomach which doubled him up.

‘Stop it,’ shouted Rupert, pulling her off.

‘It’s a lovely film,’ screamed Tabitha. ‘It’s all about ladies licking each other.’

‘I’d better come and have a look,’ said Rupert.

He returned, grinning. ‘Marcus was right. It’s a blue film about Lesbians.’ He threw the video on the sofa beside Cameron. ‘We must have a watch later.’

She was wearing a sleeveless T-shirt, and he slid his hands inside caressing her armpits, then feeling for her breasts. It was ridiculous the way he could turn her to jello.

‘I don’t fancy your bedroom without a lock on it,’ she said. ‘The only safe place with this mob around is the john.’

More shrieks issued from upstairs, followed by a crash on the terrace outside. Going out through the french windows, Rupert found the remote control with all its entrails spilling out.

Cameron stormed upstairs. She’d been looking forward to watching Dido and Aeneas on Channel Four later, and now they’d be stuck with BBC 1.

‘Why did you chuck that out of the window?’ she yelled at Tab. ‘I know it was you.’

‘Marcus won’t let me watch Amityville,’ sobbed Tab. ‘I hate him! I hate him!’

Rupert put her to bed screaming. Cameron was relieved at only having to deal with Marcus’s asthma attack.

‘I’m sorry about Tab,’ he murmured as she finally tucked him in.

‘Surely she doesn’t behave like this at home?’

‘Of course she doesn’t. Both Malise and Mum are quite strict, so when she comes here she sort of runs wild. And she and Daddy love each other so much,’ he added wistfully.

‘He loves you too,’ said Cameron, giving him a kiss.

Down the passage Cameron found Rupert talking to Tab, who was tucked up in bed with Paddington Bear, gloomily transvestite in the family christening robes.

‘You really ought to be asleep, Tab,’ she said. ‘Marcus says Mummy puts your lights out at nine.’

‘Marcus is a bloody sneak,’ said Tabitha, yawning.

‘Have you said your prayers?’

‘OK.’ Tab rolled out of bed. ‘Dear God,’ she prayed loudly, ‘please bless Daddy, Mummy, Marcus, Dollop and Beaver. And please give me Biscuit, if you think that’s right, God.’ Then her fingers opened a fraction. She could see Cameron still hovering on the landing, hopeful of a mention. ‘And please God, make Mummy and Daddy get married again, so I can come and live at Penscombe for always; make me a good girl, Amen.’

Cameron walked back to Rupert’s bedroom, quivering with rage. Rupert thought it was very funny. ‘Isn’t she awful? She asked me earlier why I didn’t sell my double bed as I didn’t need it any more.’

As Marcus predicted, Tab had terrible nightmares and ended up in Rupert’s bed. Turned on by the blue movie, Rupert and Cameron waited until she was asleep and then went downstairs and barricaded themselves into the dining-room.

‘I’ve never screwed anyone in here before,’ said Rupert. ‘Should we put mats down in case we scorch the table?’

In fact, twelve feet of polished mahogany is not the ideal surface on which to make love. Straddling Rupert, her knees aching, Cameron took a long time. She was just capitulating to pleasure when a bright red face, as apoplectic as any Mr Barrett of Wimpole Street, appeared through the hatch.

‘What,’ thundered Tabitha, ‘are you doing to my Daddy?’

‘I’m trying to keep him warm,’ replied Cameron through gritted teeth.

Things went from bad to worse the next day. Rupert went off to see his constituency secretary. Tab vanished to the stables and, despite Cameron sending repeated messages, didn’t return for lunch. Grimly setting out to collect her, Cameron found Tabitha, watched by an idling trio of grooms, jumping the new pony, which ground to a halt each time it came up to a large wall.

‘This pony don’t jump,’ yelled Tabitha.

‘Think of something really nasty before take-off, and then give him a good whack,’ advised one of the grooms.

Tab rode towards the wall with great determination: ‘I’m going to think of CAMERON,’ she howled, bringing her whip down on Biscuit’s quarters. The grooms screamed with laughter, and then cheered as Biscuit cleared the wall by a foot. Tabitha leapt off the pony, cuddling him and stuffing him with pony nuts. ‘Good boy, good boy.’

‘Lunch, Tabitha,’ said Cameron icily.

Even Tabitha looked faintly sheepish and ran on ahead back to the house.

There are a million children in England living with replacement parents, in fact one in seven is a stepchild, thought Cameron furiously, as she stalked back to the house. They can’t all be awful. Just fantasy. You’re doing research for a documentary on the in-coming stepmother, she told herself.

‘Where’s Daddy?’ demanded Tab as Cameron went into the kitchen.

‘Not coming back till later this afternoon.’

‘I don’t want any lunch till he gets back.’

‘Sit down,’ ordered Cameron.

‘I will if you sit down first,’ said Tab with a giggle.

Not looking behind her, Cameron collapsed heavily on to a whoopee cushion which Tab had slipped on to her chair, and which let out a succession of noisy farts. Tab screamed with laughter; even Marcus grinned. For Cameron the noise was too embarrassingly reminiscent of her encounter with their father on the balcony of her Madrid hotel.

‘You bloody children, stop winding me up.’

‘Don’t speak to us like that,’ said Tab coldly. ‘You’re not our mother.’

Cameron walked out of the kitchen and went and swam twenty lengths in the pool to work off her rage. Going upstairs, she discovered Tabitha must have changed at least four times that day and used the carpet of Rupert’s bedroom as a dirty clothes’ basket.

‘Tab,’ she bellowed.

‘Yes.’ Tab appeared from the television room, eating a Mars bar.

‘Pick up your clothes, OK?’

‘Mrs Bodkin picks them up.’

‘Mrs Bodkin is not here. Pick them up.’

‘Bloody shan’t.’

Cameron moved towards her.

‘Don’t you touch me,’ hissed Tab, her little face a mask of spite. ‘Because of child molesters like you, I’m learning karate at school,’ and, clenching her fist in a black-power salute, she shot under Cameron’s arm, downstairs and back to the stables.

A blinding headache nudged Cameron’s skull. What was the name of that silent order Charles Fairburn disappeared to the day the franchise applications went in? She took a Valium and went down to the kitchen where she found Marcus trying to clear up lunch.

He had put the roasting pan undrained in the sink so the grease floated thick and yellow on the top of the water.

‘I’m sorry about Tab,’ he mumbled.

‘You make up for it,’ Cameron said, hugging him.

‘It’s not all her fault,’ said Marcus, fairly. ‘She’s used to Daddy’s total attention when she’s here, and Mrs Bodkin fussing over her. She looked after Tab when she was a baby, you see. When Tab says she wants lunch she’s given it, and if she doesn’t like it when it arrives that doesn’t matter much either. She’s just not used to a stranger saying, “Do this, don’t do that”.’

Cameron gazed at the sea of fat, feeling reproved. ‘I’m sorry.’

‘It isn’t your fault,’ said Marcus, busily sloshing water all over the surfaces as he wiped them down with a dripping dishcloth.

‘I’m not around kids that much. How d’you relate to Malise?’

‘OK. He’s strict, but he’s fair. He’s very old. His grandchildren are older than me.’

‘Would you like your parents to get married again?’

Marcus went green. ‘No, absolutely not.’

‘Tab would.’

‘Oh, Tab gets on much better with Daddy than I do,’ said Marcus bitterly. ‘And if she was here she could ride all the time.

As Rupert probably wouldn’t have eaten at lunchtime, Cameron decided to make him a nice dinner. Just the two of them; the kids could go to bed early. Marcus chatted to her while she cooked and, when she’d finished, offered to play the piano for her. He was just playing a Chopin impromptu quite magically when Tab charged in with Wham full blast on the wireless.