The Royal Family pays tribute to the Duke of Westminster after his death at 64

The family of Gerald Cavendish Grosvenor, also known as the Duke of Westminster,has confirmed his passing at the age of 64. The billionaire landowner and philanthropist was rushed to Royal Preston Hospital on Tuesday (Aug. 9), where he died after suddenly falling ill on his Abbeystead Estate.

The duke, who was a close friend of the royal family, was estimated to have a fortune of $14.09 billion by Forbes, making him the world's 68th richest person, and the UK’s third. His vast wealth comes from estates in Oxford, Cheshire, Scotland and London; he owned 190 acres in Belgravia, one of London’s most expensive districts.

TAP TO VIEW GALLERYduke-westminsterThe Duke of Westminster has passed away at the age of 64

His 25-year-old son, Hugh Grosvenor, who is Prince George's youngest godfather, will now inherit the title and the entire estate, including the family seat in Cheshire, Eaton Hall.

A spokesperson for the Grosvenor family announced the sad news of Gerald's passing, saying: "His family are all aware and they ask for privacy and understanding at this very difficult time.

hugh-grosvenorHis son, Hugh Grosvenor, 25, is heir to the dukedom

"No further comment will be made for the time being but further information will follow in due course."

A Buckingham Palace spokesperson said: "I can confirm the Her Majesty the Queen is aware of the news about the Duke of Westminster. A private message of condolence is being sent by the Queen and the Duke of Edinburgh."

Prince Charles and his wife, the Duchess of Cornwall, are "deeply shocked and greatly saddened" by the sudden death of their friend, a Clarence House spokesperson added.

gerald-charlesGerald was a close confidant of the royal family

Gerald and his wife Natalia – godmother to Prince William – have three daughters as well as son Hugh. Lady Tamara, 36, who is married to one of William's best friends, Edward van Cutsem; Lady Edwina, 34, who is married to TV presenter and historian Dan Snow, and 23-year-old Lady Viola.

The duke was a close confidante of the royal family – Prince Charles asked him to be a private mentor to a young Prince William, who in turn asked Gerald's son Hugh to be godfather to his firstborn.

gerald-queenPictured with the Queen at the wedding of his daughter Lady Tamara

Prince Harry, Prince William and the Duchess of Cambridge are all regular visitors to Grosvenor properties, and earlier this month William and Kate used the Duke's private jet to fly to France for their summer holiday.

Gerald was educated at Harrow, and worked on ranches in Australia and Canada before serving an informal apprenticeship in property management, the BBC reports.

He abandoned his dream of a career as a soldier in 1973 on becoming trustee of the Grosvenor Estate, but signed up to the Territorial Army and in 1994 was made an OBE for his work in the volunteer force.

The duke credited himself with using his wealth to help others, and gave a great deal of support to both rural and inner-city areas with links to his estates.

In 2012, he was made a Commander of the Royal Victoria Order – a personal gift from the Queen – in addition to being a Knight of the Garter and a Companion of the Order of the Bath.

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