Charlotte carried a large glass of wine from the kitchen to the living room, and sank down into the most comfortable chair she possessed. But once she was nestled in its soft, healing depths, she found she had no strength to lift the glass to her mouth. So she slid it carefully onto the side table, and focused instead on closing her eyes and easing the weekend’s tensions and strain out of her body.

If only someone had told me, Charlotte thought, how hard it would be looking after small children, I would never have even toyed with the idea.

On reflection, Charlotte had to admit that her friends with children probably had told her. She had simply tuned them out. This response, Charlotte realised now, had not escaped their notice.

That’s why they stopped calling me so often, she thought. I’d put it down to the fact that they were embarrassed that I was still single — and possibly barren — which meant we no longer had anything in common. But they stopped calling because they knew I cared nothing about what they had to say.

Which would explain her friends’ confusion and, let’s face it, downright suspicion, when Charlotte had called and offered to mind their children for a whole day during the weekend.

‘You’re not hooked up with a white slave trader, are you?’ one had said.

The other had asked if she was in the thrall of a paedophile ring.

Once Charlotte had allayed their fears, they’d both said, ‘Are you sure you know what you’re in for?’

The truthful answer to that, Charlotte thought, which was not the answer I gave them, was no.

Charlotte had chosen these two friends because, between them, they had children the same ages as the ones it appeared she’d now be minding in Italy. Michelle and Chad had Harry, four, and Rosie, who was eighteen months. Darrell and Anselo had Cosmo, who was barely three months, and Clare and Patrick had Tom, who had just turned two. Tom’s birthday party had been a low-key affair, family only, held at Jenico’s house in Hackney. Patrick told Charlotte that Tom had been fascinated by the candles on his cake, and sat staring at them for five full minutes before Clare could coax him to try to blow them out. In the end, everyone blew on them, Patrick said. Tom immediately lost interest, and had gone back to stacking blocks in the corner and then knocking them down.

Patrick had never explained how he’d finally managed to persuade Clare to come to Italy. In fact, he hadn’t mentioned it at all; it had been Anselo who’d told Charlotte that they’d all be going, and asked her to book the flights and the rental cars.

All Patrick had said was, ‘Are you sure you’re up for this babysitting gig? I’m sure Italy’s full of women who’d be willing. We probably wouldn’t even need to pay them.’

‘I will be perfectly fine.’ Charlotte had smiled. ‘I’m looking forward to it.’

That evening, she’d rung her friends.

On Saturday, she’d minded the four-year-old and the two-year-old. They were both girls, unlike Harry and Tom, but that couldn’t be helped. Much of the day was now, in Charlotte’s mind, a pastel-coloured, glittery blur with a soundtrack of trapped cats and a faint residual smell of strawberry-scented plastic, chocolate milk and … oh, yes. That.

Possibly that was the worst moment. Possibly not. Charlotte mentally ticked off the potential contenders:

The two-year-old shrieking blue murder on the bus when Charlotte refused to take them upstairs, until Charlotte had no choice but to take them upstairs.

Missing their stop because the four-year-old had opened a packet of lollies that had been put in her Clarice Bean lunchbox by her mother (with malicious intent, Charlotte suspected), and immediately spilled the lollies on the floor of the bus. The shrieking that followed Charlotte’s refusal to scavenge for the lollies was a mere shadow of the shrieking that then followed Charlotte’s refusal to let them eat the lollies until she’d found somewhere sanitary to wash them.

Dragging two complaining girls an extra three blocks having also missed the next stop because the two-year-old was rather slow down the bus stairs, but shrieked if Charlotte so much as hinted she would carry her.

Enduring more complaints at the zoo gates because the girls were somehow under the impression (Charlotte intended to have strong words with their mother) that they were going to a fairy playground. Charlotte was not aware London had a fairy playground, but the girls were adamant.

Calming the resulting shrieks with promises of chocolate milk (forbidden at home, apparently) and anything they wanted from the gift shop.

Failing to prevent the girls from running past the vultures and other birds of prey and straight into the gift shop. Extracting the girls from the gift shop with a giant stuffed emperor penguin, a packet of glittery bouncy balls and a strawberry-scented eraser.

Carrying around the giant stuffed emperor penguin for an entire hour in twenty-five degree heat.

Handing the packet of bouncy balls (with strict instructions not to open it) to the two-year-old, who did open it and promptly lost one of the balls in the dim light of the reptile house. Charlotte, to the tune of shrieks magnified by the enclosed space, found the ball under the Gaboon viper. Its venom, she read, was not particularly toxic as venom went, but it produced it in record-breaking quantities. Charlotte fantasised about releasing the Gaboon viper.

Getting all the way to the café and then having to retrace their steps back to the reptile house because the four-year-old had dropped the strawberry-scented eraser.

Discovering why chocolate milk was forbidden at home when the four-year-old threw it back up all over the café table.

Enduring the disapproving looks and remarks from café staff and patrons as she attempted to mop up the milk vomit with a handful of paper napkins that instantly disintegrated in her hand.

Tucking the giant stuffed emperor penguin under one arm and dragging (literally, prompting more disapproving looks and remarks) the two wailing girls into the café toilets, where she ordered them to wash their hands and faces. If they didn’t know how, Charlotte reasoned, it was bloody well time they learned.

Stalking out of the café toilets with as much dignity as she could muster, only to have to return five minutes later because the four-year-old needed to go. Charlotte insisted that the two-year-old should go as well and was met with intractable refusal.

Getting to the entrance of the butterfly house, where the two-year-old announced that she wanted to go now, and before Charlotte could act, pulling down her pants and defecating on the path. All Charlotte had to deal with it was her own cardigan, which she’d brought in case the day clouded over. She wrapped the offering in fine Italian merino, and shoved it into her Orla Kiely tote. And then she told the girls that the butterfly house was closed and that they’d be going home by taxi.

Her friend opening the door to a giant stuffed emperor penguin and two perfectly chipper daughters, who jumped about and clapped their hands and said they’d had a brilliant time and could Charlotte take them somewhere again, please, please, please!

Refusing the offer of a glass of wine — her friend must have known, Charlotte decided.

Paying a second taxi fare from Hampstead to her flat in Battersea.

Dumping her cardigan in next-door’s skip.

Sniffing her Orla Kiely tote, extracting her wallet and keys and dumping the tote in the skip, too.

Oddly, today’s wrangling, feeding and nappy-changing of the six-month-old baby and sixteen-month-old toddler (her friend had bought into the old wives’ tale that you can’t get pregnant while breastfeeding) seemed like small beer.

Perhaps it was because I was in their home, and did not have to leave, thought Charlotte. I did a lot of trekking between rooms, and my calves are aching from having climbed what feels like two thousand stairs. And I sang The Wiggles’ ‘Hot Potato’ song so many times it felt as though I’d been lobotomised. But really, she decided, when you’ve wrapped human faeces in your best pink merino wool cardigan, what could ever daunt you again?

Those who witnessed the first meeting of Margaret Thatcher and Ronald Reagan probably held their breath, too, thought Darrell. Either the pair was going to bond like Damon and Pythias, or everyone in the free world would need to start digging bunkers in their back gardens. On the upside, Michelle and Clare probably didn’t have access to nuclear weaponry. Even so, that was no guarantee of safety.

Darrell was at her kitchen table, with Clare and a laptop. Cosmo was asleep in his cot upstairs and Darrell had one ear tuned to the baby monitor on the bench, which was emitting the quiet hiss that suggested all was well. Tom was on the playmat in the corner, banging blocks into the board with the holes. Clare had brought the toy with her only because, Darrell suspected, she’d tried and failed to prise it from him back home.

It was strange having Clare in her house, Darrell found. Partly because her house was, in fact, Clare’s. When Darrell had first come to London, she’d rented the house from Clare for a pittance because it was, at the time, undergoing renovations. That was how Darrell had met Anselo. He’d been the builder tearing the house apart. The new kitchen they were now in was his creation. He did a good job, Darrell thought. It’s a lovely room to spend time in.

But the main reason Darrell found Clare’s presence strange was that Clare never visited, and certainly not with Tom. She only took Tom to the café on Saturday mornings because Patrick insisted. Clare’s proviso was that Patrick did all the work of looking after his son when they were there. Not that this meant Clare ever relaxed. Even now she has one eye on him, Darrell observed, just as I have one ear on the baby monitor.

Clare’s attention was ostensibly on the laptop screen, where a black square should have revealed Michelle’s face five minutes earlier. This was the reason for Clare’s visit — to meet the woman she’d be sharing a villa with for four weeks.

Or no weeks, thought Darrell, depending on how this meeting went. Provoked by the slightly disturbing thought of Reagan and Thatcher, she remembered a line from a Patrick Campbell story — something about two people who would either get on like a house on fire … or an ammunition dump exploding. As they waited for the black square to come to life, Darrell found her insides already ducking for cover.

From the laptop speakers came a tinny, faint, impatient voice. ‘Hello? Where are you?’ Then to someone else: ‘Non, non, je suis fine! Bugger off!’

‘Press the video button,’ said Darrell.

‘Hang on, hang on! This computer c’est freaking stupide …’

The square was suddenly and hugely filled with face.

‘Jesus!’ said Michelle, quickly sitting back. ‘For a second there, I thought I’d turned into Minnie Driver!’

Darrell smiled. She’d always thought Michelle’s black straight-cut bob made her look more like a silent movie star. The bob was a little uneven around the edges, Darrell noted. Michelle had limited tolerance for waiting, so if the French salons were booked up, it was more than likely she’d grab the nearest pair of scissors and do it herself.

‘Can you see us?’ Darrell adjusted the screen so both she and Clare were visible.

‘Yes, yes!’ said Michelle. ‘No thanks to this stupid internet café. C’est full of beardy French-muttering Gen Y buffoons.’

‘Are you in Paris?’

‘Ha!’ said Michelle. ‘Now that I’ve insisted we haemorrhage moolah on this Italian jaunt, a decent stay in Paris is pas possible. We went there for one day. Spent it eating overpriced croques monsieur, and staring at the bottom of the Eiffel Tower, as the queues to go up were incroyable. No, the Lawrence family is now sharing one room in a pensione in Reims.’

‘Reims is very pretty,’ said Darrell. ‘Anselo and I went there on our big trip.’

‘Not this bit of it,’ said Michelle. ‘C’est une dump grande. But let’s not dwell. Hello, you must be Clare.’

‘Hello,’ said Clare with a frown. ‘Where are your children?’

‘Out scarfing pain-au-chocolat with their father, I imagine,’ said Michelle. ‘They’re supposed to be going to the local marché to buy food, but Chad’s French is even worse than mine, so he’ll be putting it off till the last minute. Numbers are his main problem. After deux, he’s stumped, which is un peu limiting when there are four of us.’ She smiled fondly. ‘Poor Chad. He’s spent this whole French excursion feeling like un retard massif.’

‘I’d hoped to see them,’ said Clare, the reproof evident in her voice.

Darrell cringed, but Michelle’s smile only widened.

‘Worried they’ll gang up on Tom?’ she said. ‘That he’ll be like the doomed fat kid in Lord of the Flies?’

‘Well …’

Darrell had never seen Clare truly discomfited before. She realised she was enjoying it, and instantly felt a twinge of guilt.

‘Don’t fret,’ said Michelle. ‘Harry is a mild-mannered sweetie like his father. Rosie, on the other hand, is from one of the seven circles of hell. But I can always tie her up and gag her if she starts creating.’

Clare did not look entirely convinced that Michelle was joking. ‘Your husband was a banker, I hear?’ she said.

Pursuing a different line of interrogation, Darrell noted. She wondered if the British government had ever thought of enlisting Clare in the war on terror. It’d be over in half a day if they did, she decided.

‘Chad was indeed a banker!’ said Michelle cheerfully. ‘Until he had the brain fart that brought on this trip. But at the end of this year, we’ll go back to the family home, which we’ve remortgaged to the hilt, and I’ll fend off the bailiffs with a shotgun while he goes on the job hunt again. Unless he decides he’d prefer to live in Cuba and write short stories. In which case, I will aim the shotgun at his feet and make that sucker dance.’

‘Or you could go back to work,’ said Clare, folding her arms.

‘You’re right!’ said Michelle. ‘I could earn crap-loads if I went back to being a corporate lawyer. I should think about that … OK, I did. Nope! Mommying’s the only job for me. How about yourself? What did you do before you lost all sense of an individual identity?’

Clare hesitated briefly. ‘I was in PR.’

‘Yowzer!’ said Michelle. ‘The only life form lower than my own past career! Oh no, wait. I forgot about people in advertising.’

Then before Clare could respond, Michelle said, ‘Tell me, what does Charlotte Fforbes with two fs look like? I have a picture in my head of Samantha Bond in one of her typical roles. You know — cool, elegant, utter bitch.’

Darrell laughed. ‘I’ve never met her. Anselo likes her, though, so she can’t be that bad. Mind you, you’ve pretty much described his last girlfriend. Except for the bitch thing, I suppose …’

‘Exes are always bitches,’ said Michelle. ‘Or bastards, depending on what side of the fence you’re on. I begrudge every bit of time that some other bint who wasn’t me spent with Chad. I even begrudge his mother.’

‘That is Freudian and creepy,’ said Darrell. ‘You should be ashamed.’

‘We both know how unlikely that is, don’t we?’ said Michelle.

‘Fascinating as this is, shouldn’t we be more concerned about Ms Fforbes’ childminding qualifications?’ said Clare. ‘I have only Patrick’s vague assurances that she has any, which makes me suspect it may be a big con on her part to score a free trip to Italy.’

‘She’s about to take on one infant, two small boys and a foul fiend,’ said Michelle. ‘Rosie alone will be an object lesson in how unwise it is to tell big, fat fibs. It’ll be like the darkest Victorian morality tale come to grisly life.’

A noise came from Clare, but it was a few seconds before Darrell realised it was a chuckle. Clare did have a sense of humour, Darrell conceded. But it was generally expressed in a sarcasm that could wither fruit on the branch. Darrell couldn’t remember for the life of her the last time she’d heard Clare laugh.

On the screen, Michelle was laughing, too, and Darrell felt another twinge. This time, it wasn’t guilt. As she watched Clare, her landlady and wife of her husband’s boss, in whose company she’d never felt entirely equal or at ease, bond with Michelle, her best friend since forever, Darrell felt the sharp finger-poke of jealousy in her ribs.

Michelle’s mine, she thought. But even as she did, another thought rode over it. Clare wants everything her way, Darrell’s mind said, and Michelle has always done exactly as she wants. If the two of them decide to become tight, I’ll be three’s-a-crowd on the outer, and I doubt I’ll have the energy or confidence to change that.

Darrell looked over at the baby monitor, which was still silent. Well, Cosmo, she thought, on this holiday, it might be just you and me, so I’d better get used to it.