Back we go to Africa. Five months at the bottom of the world and I know that I can’t live there. Jasmina’s with me on this one (she’s still easily persuaded) and Kinvy’s not bothered, but Gregor and Nick are still worryingly enthusiastic about the place. They both love the wilds of New Zealand, its fishing, rugby and general manliness. But it is too far removed from the feisty hurly-burly of the world for me. I’m hoping that they will see the light, so to speak, once we get back to Kenya.

Auckland, Perth, Johannesburg, destination Nairobi. We are thrown back into the chaos, pollution and poverty that make this a city to avoid. Huge marabou storks nest in the street trees, grey and grimy, just like the city. Hawkers try to sell pillows, metre rules, plastic coats – but we won’t open our windows in case we are car-jacked. So different from New Zealand. A drawback, I admit, to my pair of Kiwi-idolisers. But there is a special mustiness to the air that we associate with Africa, and we all greet it like an old friend. We are back in a place that we love, even Nick is quick to agree (Gregor is on strike).

I am on the brink of a birthday that ends with a zero and my parents have flown out from Devon to celebrate. This is their first time in Africa, and they are dressed in their new safari gear, head to toe in khaki, ready for the wilderness. The children are ecstatic, their delight in seeing their grandparents is something special and we both take note.

For the Big Day itself, we have booked ourselves on a camel safari – several days’ walk in extreme heat through the emptiness of Samburuland, accompanied by 20 camels and their herdsmen, our fantastic guides Helene Dufresne and Pete Ilsley, a couple of tents and a lot of water.

Kinvy is camel-back for the journey and immediately masters the uncomfortable art of falling asleep on an undulating hump. The Samburu have given Helene a hill that overlooks three dry river beds and a backdrop of barren mountains. My birthday is heralded here in absolute isolation and splendour. We sip Pimms and champagne as we watch a sparkly satellite curve its way across a vast sky. Apart from us, there is nothing of the Western world and we agree that this is staggeringly wonderful.

After the desert, we crave the sea and take a seven-hour hair-raising drive across the back country to Watamu, a ramshackle village that perches untidily on the beautiful Kenyan coast. Locked behind our security grilles that night, clutching the portable panic-button that we were handed on arrival, hugger-mugger with the children since we won’t let them sleep separately caged and padlocked – I’m also worried about Granny and Grandad, but there is no room for them in here with us – I reflect on the fact that I may have had an overly romantic vision of holidaying in this part of Kenya. I can’t help but feel that we would be safer back in Cornwall. Certainly, the neighbours seem less sinister.

A sense of trepidation has begun to creep into our travels. Botched dental treatment in Australia means that I have to go back to England for more, and we have decided to press the pause button while we fleetingly visit schools around the West Country. After a year away this is providing an unwelcome dose of our old reality, but we are acutely aware that we need to make a long-term plan for the children. Schools, friends, a home: decisions about all of these are urgently called for. The list of reasons to live in England is growing, so we have to go back for a look.

Allowing a mere week to resolve some rather monumental issues, we intend to slip in and out, barely noticed, before heading off to the Continent. We have decided, belatedly, to try to imbue in the children some appreciation of the cultural and historical marvels that may eventually be on their doorstep, and we are planning a grand tour. Gregor, in particular, needs convincing. “When are we going back to New Zealand?” he asks. “Not,” I reply through gritted teeth, “for a very long time.”

Read previous dispatches from the Tims’s round-the-world trip at timesonline.co.uk/timsfamily.

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