The Sahus appear to be the perfect family. The father Santosh is a millionaire, his wife Surabhi, a former beauty queen travelling with their kids to celebrate the A-Level results of their oldest son before he goes to university.

Their youngest Syna Kumari Sahu, at just 13, is the youngest Briton still missing in the flooding disaster in Nepal which has killed almost 1,000 people and counting.

Santosh’s brother Murali told all his family, back in London, can do is wait by the phone for any updates and share their photo on social media.

He said: ‘We spoke for the last time over the phone on Tuesday. They were enjoying themselves in Khatmandu.

‘We really miss them. It’s been a week and we still haven’t heard anything from them. The embassy have been helping us but there is no information.’

Getting emotional, he addressed them directly: ‘For God’s sake, please call just once. We are praying for you every day.

‘Brother, I just want to hear your voice. I need to hear you say name – I love you.’

The family had been on a once-in-a-lifetime trip to Mount Kailash, a religious site for Hindus and Buddhists in Tibet. Their last known photo shows their youngest Syna flashing a peace sign and smiling with the other Brits and South Africans on their tour bus. Their WhatsApps went offline just hours later after crossing the border into Nepal.

Spandan had just finished his A-levels at Royal Grammar School, Guildford, and was preparing to study philosophy, politics and economics at university. The trip is their last quality time together before he moved out of their family home.

Mahadev Semwal, who lives in Reading, described his friend Santosh as ‘someone who came from a very humble background and built his life through determination, hard work and an extraordinary entrepreneurial spirit.’

As for his wife Surabhi, he added ‘she is equally remarkable. Together they are a wonderful couple and devoted parents. Their son, now 18, is exceptionally intelligent and full of life, with a bright and energetic personality that brings great joy to the family. Their daughter is always eager to learn, explore new ideas and understand the world around her.

‘Santosh takes great pride in both of them, supports their dreams and always makes time to guide and encourage them, no matter how demanding his work may be.’

Nepal’s rescue teams, helped by Chinese and Indian experts, stepped up efforts on Monday to reach hundreds of people believed to be stuck inside blocked hydropower project tunnels in the aftermath of last week’s Himalayan flood.

The unprecedented deluge of ice, rock, mud and debris carved a trail of destruction in the country’s valley towns and villages, as well as across the border in China, on Wednesday, killing more than 900 people, with nearly 5,000 still missing. More than 500 tourists, including 33 Britons, are still said to be missing.

A glacier collapse is thought to have triggered the disaster.

Hundreds of bodies, many unidentified, have been buried in shallow graves as they began decomposing in the humid weather in the plains of the Himalayan country after being swept down the mountains by the torrent.

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