Having realised that the long summer school holiday won’t go on forever (after all), I decided it was time to take the children up to London, and give our hosts, their grandparents, a well-deserved day off.

An added incentive was that my BF agreed to come with us to Covent Garden’s London Transport Museum – and there was also the inkling that we might be able to sneak lunch in at my favourite sandwich shop, Pret a Manger.

But apart from that, it was all for the good of the kids – honest.

The funny thing about taking BB and LB on day trips is that, for them, it’s the journey that’s the exciting bit. Not the destination, and certainly not lunch. It’s all about the getting there – on South West Trains, and the Northern Line.

They didn’t mind one bit that the train to Waterloo was really crowded and so we had to stand right by the toilet – they got to watch people going in and out the loo and could even time them.

Given that in the UAE, apart from the new, driverless metro, there are no railways – and BB is obsessed with trains – it makes sense that the Woking-Waterloo service is a thing of amazement for him. On passing through Clapham Junction, his eyes nearly popped out his head and as we went down the escalator to the underground, I promised him we’d travel on the deepest line.

Not such a thrilling ride if it’s your daily commute, but we got some smiles five minutes later, with both kids pressing their noses against the window, peering out at the tunnel, absolutely loving trundling through the darkness.

The trouble with their enjoyment of train journeys is that when we reach our destination, they usually just want to turn around and go home again. But, today, I’d thought of that: The Transport Museum – ta-daaa! They could even drive a tube train! A brilliant, foolproof plan, surely.

And it was a success, until it came time for lunch, and we made them walk to Leicester Square (all of five minutes), triggering a tirade from my hungry oldest son. “But I can’t walk, my legs have died. This is my baddest day ever.”

Kids, eh – I could have sworn that a few minutes earlier he was energetically running around and playing inside a bus exhibit as happy as larry.