It happens almost overnight. One day, he’s licking pureed food off a plastic spoon; the next he’s wolfing down the contents of the fridge, and gnawing at the fridge door if you momentarily take your eye off the grocery shopping.

And quite frankly, it’s terrifying. Not to mention expensive. While I watch what I eat and try to be healthy, my eldest son has developed an appetite so huge, I feel as though I’m responsible for feeding the ten thousand. It’s been the equivalent of watching a picky lapdog reinvent itself into a hungry elephant with hollow legs.

This afternoon, I unexpectedly finished work early, and had rose-tinted visions of happily spending the afternoon with the children, while catching up on some chores. Son 1’s school bus pulls up outside, the front door bursts open, and a ravenous Great Dane bounds into the house.

And that’s just breakfast! Does it cost £12,000 more to bring up a boy than a girl because they eat more?

“MUM, I’m HUNGRY!” Son 1 yells. This, I expected. And I’m ready. Those after-school hunger pangs require an immediate carb-injection or we all suffer. But, then, less than an hour later:

“Mum, can we have dinner now? I’m soooo hungry!” It was 4.30pm, and while I did try to tell him to wait (and provided fresh fruit in addition to the after-school snack), it was clear our household wouldn’t be a happy place until he was drip-fed more calories.

It’s not that I mind preparing dinner so early, it’s just that I know he’ll forget he’s already eaten it by 7.30pm, and start circling again in hunt of another meal.

There was a telling prelude years ago, when Son1 was little and one afternoon desperately wanted bananas. He threw a tantrum so bad it left me with little choice but to head straight to the fruit stall at our local market. To my astonishment, he demolished seven bananas. That’s when I realised that feeding boys is all about quantity and planning.

A survey by Halifax bank on the cost of bringing up children showed parents shell out over £12,000 more to raise a boy to the age of 11 than a girl. This difference was put down to extra sports kits, even wear and tear of furniture caused by rambunctious behaviour. But I think the reason for the higher price tag is obvious: the grocery bill.

Since my son’s appetite became so monstrous, I’ve had to take all sorts of extra measures. We have a truck deliver us food. The grocery shopping was becoming too burdensome, too frequent. So, now, I order online and Geant brings everything to the door. If our nanny or I cook pasta, we no longer make enough for one meal. We cook the whole packet and send the leftovers into school (sandwiches weren’t cutting it). Cereals are continually replenished (a small victory being he prefers Weetabix, even Bran Flakes, over the sugar-and-marshmallow-filled varieties). Milk is now bought in 3-litre cartons, and bread restocked nearly daily so I can throw them toast.

Motivating families to lose weight, Dubai style

But I worry about it. I had insulin-dependent diabetes during both pregnancies. Could something be wrong? We live in a country where obesity is a big problem – so much so that the government runs weight-loss campaigns in which gold is handed out to successful ‘losers’. Controversially, this year’s initiative, Your Child in Gold, includes all family members, even chubby toddlers. (It’s very Dubai, isn’t it? Register, shed kilos and get gold.)

Friends with boys report a similar unstemmed tide of carbs, calories and cash, so I’m hoping Son1’s appetite is normal for a child growing so fast. DH is tall, and I think Son 1 – who’s already nearly up to my chin – is heading for great heights too. Like a very hungry caterpillar, he appears to fill up on food, grow plumper, then suddenly shoot up two inches. The growing pains, however, are mine.