It was a Gucci bag. It looked expensive. It didn’t look like the sort of thing you wanted your two-year-old son to spill a bucket of sea water over. For a moment, I thought about waking up its owner, but she looked so peaceful, spark out on her sun lounger. I quietly emptied what was left from the bucket into the moat of Conor’s sandcastle and took him off for a swim.

Small children and high fashion are not a natural combination, but then something strange is happening at the Caribbean’s hippest hotel. Carlisle Bay, that outpost of chic minimalism in the tropics, has been invaded. A barbarian horde of sprogs has stormed its neat modernist blocks, dive-bombing in the free-form pool, spattering aïoli across the starched tablecloths and wetting themselves on the designer sofas. I know this because two of those sprogs were mine.

It wasn’t supposed to be like this. When Carlisle Bay opened three years ago, its urbane design was revolutionary for the Caribbean, and it attracted the same crowd as its stylish sister hotel, One Aldwych, in London — media types, switched-on City bigwigs, zeitgeist surfers. All of them, of course, grown-ups.

A few months ago, however, CB opened a kids’ club. Now kids, as any parent knows, are not minimalist. They are maximalist. They need lots of stuff and rub jam into expensive rugs. They are noisy and messy, and do not know what zeitgeist means. It sounded like a culture clash of motorway pile-up proportions. So, ever the rubberneckers, Jaqui and I packed Conor and four-year-old Molly off to Antigua to take a look.

THE CULTURE clash materialised the moment we arrived in our room. The aesthetic at Carlisle Bay relies on very few, very beautiful things. An orchid was carefully placed on a low table; two soulful photographic still lifes sat on an expanse of grey wall; there was a designer chair, a designer bed, a flatscreen TV, and that was about it.

Four minutes after Molly and Conor got in there, the place looked like Toys ‘R’ Us after a gas explosion. Dolls, rubber rings, crayons, dummies, half-chewed biscuits, Thomas the Tank Engines and comics were scattered everywhere. Conor was pouring juice into the orchid pot, and Molly was 2ft above the luxurious bed’s Frette linen sheets, testing its bounceability. And I knew from bitter experience that they were only warming up. How much havoc would they wreak once they got out among the designer frocks?

The answer, of course, was plenty — but they weren’t the only ones. There were dozens of kids there, most of them preschool age. In fact, it rapidly transpired that there is no longer one Carlisle Bay, but two; and, while it would be stretching a point to say they’re actually at war, it’s always more fun to stretch a point, so I will.

BATTLEFIELD ONE: the restaurant On our first morning, we piled into the resort’s main restaurant, Indigo, and from the egg soldiers and parental oaths flying through the air, we could tell the children had gained the upper hand. The staff did their best to seat adults at the prime tables next to the beach, away from the scrum in the centre of the room, but their tactic was dubious: a constant traffic of toddlers threaded its unsteady way from inner tables to the beach and back, trailing sand and soggy rusks between the honeymooners like a living warning of the perils of procreation. Don’t get too frisky, they seemed to say, or you might end up with something like me.

Lunch was a little quieter, and by evening, the adults had regained control and peace reigned — mainly due to the hotel’s clever tactic of staging a kids’ high tea at 5.30, thus getting the bunfight out of the way early. Verdict: an uneasy truce.

BATTLEFIELD TWO: the beach The front line was clearly drawn. Families tend to stay in the beach suites at the western end of the resort, and the sand in front was fortified with castles and occupied by a crack regiment of under6s armed to the teeth with inflatables in primary colours. At the eastern end, in front of the adult enclave of ocean suites, grown-ups lay watchfully on their loungers, ready to repulse incursions with a volley of withering glances. (When not on sentry duty, the adults read a lot — mostly the paperback hit We Need to Talk About Kevin, the story of a badly behaved child who grows up to stage a school massacre. Possibly you could read too much into this, but still.) In the week we were there, the kids seemed to gain 20 yards. At this rate, they’ll be at the watersports shack by Easter. Verdict: tots on the advance.

BATTLEFIELD THREE: the pool Here, the children’s tactic is simple: blitzkrieg. While a notice warns “no diving”, it says nothing about jumping from the edge, accompanied by ear-splitting shrieks and yells of “Look at my splash, mum!”. Occasional adult raiders didn’t last long. One nice-looking gay couple managed two hours, but finally retreated after being soaked for the fifth time. Verdict: total victory for the kids.

“IT HAS been a bit of a surprise,” Carlisle Bay’s general manager, Andrew Hedley, says a touch ruefully. “This wasn’t intended as a family hotel, but some weeks about half our guests have children with them.

“It’s a generational thing. People now in their thirties grew up with a certain idea of a stylish hotel, and they’re not prepared to compromise on design. So they bring the kids along. And we’ve tried to make them welcome.”

Well, you can’t fault them on that. Milk and cookies waiting in your room on arrival, Bambi in the hotel cinema and Shrek on the DVD menu, baby monitors on demand and a brilliantly equipped kids’ club: all that, and a top beach, makes it a fabulous place for kids. Having broken new ground by bringing minimalism to the Caribbean, CB is morphing before your eyes into another first: the designer kids’ hotel.

Not that it’s going to happen without a struggle. Having a drink in the bar on our last night — baby monitor discreetly hidden in Jaqui’s bag — we got chatting to a couple in their forties. They were charming, but . . .

“You know,” said the woman — she looked familiar, come to think of it — “this place would be perfect if it wasn’t for all the bloody kids running around. I’m sure one of them poured sea water on my bag today. It’s ruined. Why do people bring children to a place like this?”

We bought them a drink — it seemed the least we could do — but kept the monitor out of sight. The battle will continue, but it looks to this reporter as if the writing is on the wall — and it reads, in big, badly formed letters, “kidz rool”.

Travel details: Carrier (0161 491 7620, www.carrier.co.uk) has a week at Carlisle Bay, from £2,231 per adult, B&B, or £5,900 for a family of four, including British Airways flights from Gatwick, transfers and afternoon tea. Alternatively, try Kuoni (01306 747000, www.kuoni.co.uk) or ITC Classics (01244 355300, www.itcclassics.co.uk).

Spoil ’em rotten

NOTHING RUINS an expensive holidayfaster than bored tots or child-hating staff — so which other five-stars genuinely welcome kids?

LE SAINT GERAN, Mauritius

Seriously posh, but seriously child-friendly, too: a great play area, a cracking kids’ club and food they’ll actually eat. www.oneandonlyresorts.com

RITZCARLTON, Dubai

Highly regarded kids’ club with imaginative activities — junior manicures, anyone? — free gifts, souvenirs and fish fingers on the extensive children’s menu. www.ritzcarlton.com

FOUR SEASONS, New York

Big city five-stars can be the snootiest of the lot, but the Four Seasons scores for its kids’ DVDs,baby bathrobes, children’s menus, toys and baby-sitters — there’seven a 17-year-old “teen concierge”.www.fourseasons.com

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