Holly and Bianca could have been any one of our children

It starts with a passport. An open-ended ticket. A backpack crammed with quick-dry undies, optimism and parents’ hearts.

You wave them off, smiling wonkily as they disappear blithely through airport doors.

Bianca Jones (left) has died, and her friend Holly Bowles remains in a Thai hospital after consuming the methanol-laced alcohol.

This is what you wanted for them, you tell yourself, your husband’s hand a lifeline. This is the independence you’ve prepared them for.

But as you drive away – the car emptier than before there were no kids at all – the thought is there: what if I never see them again?

The devastating story of Holly Bowles and Bianca Jones has revived that fear for parents everywhere. I can think of nothing but the two young Melbourne women, their vibrancy and promise destroyed by methanol-tainted drinks at a Laos bar.

“Every parent’s worst nightmare” is a cliche, but there’s no better description of a pain too big to put into words. And it feels so immediate, so personal, because it could happen to anyone’s child.

This isn’t the distant tragedy of a faraway war or earthquake. This is the terrifying randomness of life, crashing down as the normality of summer kicks off. Holly and Bianca were doing something millions of us have done before, something we’ve encouraged our kids to do: explore the planet, make memories, broaden perspectives.

Leaving home to fling ourselves into the unknown has been a rite of passage for many Australians for decades. We save up, become obsessed with backpack sales, think we’re bulletproof. Schoolies is on right now, with the latest wave of school-leavers on the loose around Australia.

My goddaughter Maisie is studying in Wales, my friend Pies’ daughter Ginger is nannying in Canada. My cousin Brett posted an airport shot days ago as his son left to chase snow for two years.

“Bloody kids,” he wrote. “You feed them, shelter them, educate them – then they leave! Safe travels Leo. We will all miss you terribly but hope you have a great adventure.”

I’ve been that fledgling, my mum worried about sex traffickers, me concerned only with the wodge of travellers’ cheques in my money belt. I’ve been that parent treasuring the last hug, warning about dirty tattoo needles in Thailand and overly solicitous European strangers in France. So far, the worst that has befallen my kids has been one son leaping from a window to escape gem smugglers in Sri Lanka, and an elderly woman passing away in the plane seat next to Sadie.

Travel is a way to grow, to build resilience. As parents, we prepare kids the best we can. We teach them to avoid dark alleys and sleazy men, to call home if something doesn’t feel right, we buy them travel insurance and lecture them about scooter hire.

But the world is unpredictable. Serves up a night in a bar that can turn deadly in a random, unbearable way.

So how do we reconcile this? How do we keep them safe while letting them find and use their wings? Truth is, we can’t. The world is as dangerous as it is incredible, and part of growing up is learning to navigate that dichotomy of vulnerability and freedom.

Maybe the answer lies in education, in pushing for stricter regulations and better awareness of risks like methanol poisoning. In people everywhere being better, in seeing young travellers as someone’s beloveds instead of commercial opportunities.

Or maybe, it’s just about holding them close before they go and reminding them that no matter where they are in this roulette-wheel life, we’re with them.

As parents, we want to give our kids the world. We want them to have the freedom to explore and learn. But Holly and Bianca’s plight is a terrible reminder this freedom comes with a cost – that fear we might lose them along the way. And still, we let them go. Because to hold on too tightly would be to deny them the very thing we’re so afraid of losing: the chance to live fully.

So we watch them board planes, fingers crossed they return with stories of adventure, not survival. And that wherever they go, the world will be kind.

Kate Halfpenny is the founder of Bad Mother Media and a regular columnist.

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