I can only conclude that you're having an affair!" my grandmother bellowed across her paella, waving her glass of Rioja perilously close to my new white holiday dress. There were 19 members of our family, spanning four generations, all sitting round the restaurant table on that balmy Spanish evening. But her eyes were firmly locked on her son – my father – with whom she was apoplectic for flirting with the friend that my cousin had brought along on our family vacation. It was at that moment I realised our holiday was beyond redemption.
My father has always been a flirt. But while his mother normally witnesses his inevitable beeline for women for the odd evening only here and there, we were by now on day nine of a holiday in a remote Spanish villa where there was little to do other than observe each other and our idiosyncrasies.
Believe it or not, we're a close family. We range from five to 84 years old and we genuinely enjoy each other's company. Some of my fondest memories are times spent altogether, laughing until my sides split. Which is why a fortnight's holiday seemed like a genius plan. And for the first... now, let me count... six days, it was everything we wished for. The views were second-to-none, the villa was straight out of an interiors magazine, the pool was vast, the company as good as ever.
But as the first week ended, the dynamics took an unexpected turn. The family's two keen cooks were getting tetchy about who was going to cook what and there were issues about some family members never seeming to have any euros to hand when the supermarket bill was divvied up. Why couldn't the men in the family ever help with the mountains of washing-up? And couldn't cousin Bill's second wife refrain from boozing long enough to notice her two pre-school children nearly fell into the pool twice?
Multigenerational holidays are on the increase. A study by Travelsupermarket.com has found that more young adults than ever are holidaying with their folks. Other recent research discovered that nearly three million families will go on a "greycation" this year – a term used to describe three generations holidaying together. Holiday companies including Center Parcs, Blue Chip Vacations and Explore predicted that holidaying with the extended family would be huge this summer, and the travel industry body Abta confirms that large family bookings (from groups of five to 10 people) accounted for nearly half (41 per cent) of all passengers last year.
My own experience begs the question why. The first answer is simple – money. Travelsupermarket found that younger people aren't known as the piggy-bank generation for nothing. Nearly a quarter of adults admit their parents have paid for or supplemented the cost of a holiday since they turned 18. But hold the tut-tutting just because you're older. One in 20 confesses their parents still pay for their holiday, regardless of their age, and 37 per cent say that's a major reason for sharing their hols with their kin. The "greycation" research is similarly disheartening, with one in five respondents admitting that they will take a UK trip with all the family expressly to save money. Worse still, 18 per cent of parents admitted the grandparents were there to provide free babysitting.
But take heart. Almost half said their aim is to increase time together between children and grandparents, with many stating that they were returning to a family tradition from previous generations. Likewise, nearly half of those interviewed by travelsupermarket.com claimed they travelled with their parents because they enjoy spending time with them.
"Why wouldn't I do it?" asks Dean Evans, 24, genuinely bemused at the question. Evans, who lives in North Wales and holidays with his parents and his 18-year-old sister every summer in Spain, says: "I pay for my flight, but that's about it. They cover pretty much everything else, so it winds up costing me under £200 for a nice holiday – and it is a nice holiday because I get on with my parents really well."
There are things that make it work, he admits – a spacious villa, with the emphasis on spacious, and the agreement that everyone does their own thing if they want. Then comes his most telling statement. "I still live at home, so in many ways, a holiday is business as usual."
That's the thing with Generation Y. Almost one in five graduates in their late twenties lives with their parents, while 20 years ago, only one in eight returned home. Even those with offspring who have moved out are more likely than ever to be helicopter parents, so called because they hover closely overhead, rarely out of reach. If they're not texting their 27-year-olds to remind them of a dental appointment, they're (you guessed it) booking their holidays.
"We are much more hands-on parents these days and very involved in our grown-up children's lives, both emotionally and financially," says Eveleen Hatch, whose 19-year-old daughter, Emily, and her boyfriend will accompany them to Kos later this summer.
"I don't want to get any older and the idea of going on a family holiday makes me feel like one of the 'children' still," admits Emily. "As for my boyfriend, he can't wait because he's an only child and loves my family."
Those in their thirties, forties and even fifties can be in for some rude surprises too, says the psychologist Linda Blair. They may discover unexpectedly old patterns kicking in as they're asked questions such as "Are you really going to wear that?" and "Don't you mind your daughter staying in bed all day on holiday?" Then there are the in-laws...
The key is to know why you're going, she says. If, for example, a multigenerational holiday is your idea of hell, but you think it's good for the grandparents and grandchildren, decide to put up with it, just as you'd put up with Christmas, or send your kids on holiday with them while you and you partner sneak off to a boutique hotel.
Reduce expectations, she adds. People are away from their normal routine, beds and mealtimes. "Use humour," she advises. "Not sarcasm, but respectful jesting to take the edge off potential conflict."
For 24-year-old Tom Mitchell, who accompanied his 27-year-old brother and their parents to Majorca last year, part of the trick lay in agreeing to try to "right" the things that used to go wrong on childhood holidays. "My parents would always row about map-reading. Now they let us navigate," he says. The family also cleverly agreed to road-test the idea in advance, with a long weekend away together.
For my family, get-togethers are back to being enjoyable. We even laugh about (most of) that holiday and I, for one, choose to remember the many, many fun bits. But there are some wounds from that vacation that will never heal, and, just sometimes, I do wonder if it was worth it for the sake of a fortnight.
Tips for a harmonious holiday
1. Agree who is paying for what from the early planning stages.
2. Choose a destination which offers something for everyone. All-inclusive resorts are good at getting the balance right, and self-catering is good for lots of people who want to do different things.
3. If you opt for a villa, get one with all the mod cons, especially a dishwasher.
4. Rather than hiring one larger car, get more than one smaller one.
5. Consider bringing friends into the equation, especially for the benefit of the younger generation. It will keep the rellies on better behaviour, and prevents anyone from feeling they are gatecrashing their parents' holiday.
6. Consult your partner. He or she may not share your enthusiasm about spending two weeks with 17 of your nearest and dearest, and the undercurrent of resentment could spoil it for everyone.
7. Don't sweat the small stuff. Not every comment or instruction from a relative is worth fighting over.