Britain's Prince William, Duke of Cambridge reacts, as Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., speaks to club officials during his visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Britain's Prince William, Duke of Cambridge and Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., walk during a visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Britain's Prince William, Duke of Cambridge and Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., meet with club officials during a visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Britain's Prince William, Duke of Cambridge gestures as he speaks to Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., and club officials during his visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Britain's Prince William, Duke of Cambridge gestures as he speaks to Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., and club officials during his visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Britain's Prince William, Duke of Cambridge reacts as he speaks to Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., and club officials during his visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Britain's Prince William, Duke of Cambridge gestures as he speaks to Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., and club officials during his visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Britain's Prince William, Duke of Cambridge reacts as he speaks to Rob Morris, Co-Owner of Silver Jubilee Park and Vice President of Hendon F.C. and Edgware Town F.C., and club officials during his visit to Hendon FC, as part of the Heads Up mental health campaign at Hendon F.C., in London, Britain September 6, 2019. Tim P. Whitby/Pool via REUTERS 

Indian Prime Minister Narendra Modi touches the feet of a saint during Akshardham temple's silver jubilee celebrations in Gandhinagar, India, November 2, 2017. REUTERS/Amit Dave TPX IMAGES OF THE DAY 

Hindu saints perform rituals to celebrate Akshardham temple's silver jubilee in Gandhinagar, India, November 2, 2017. REUTERS/Amit Dave TPX IMAGES OF THE DAY 

Indian Prime Minister Narendra Modi arrives at the Akshardham temple to celebrate the temple's silver jubilee in Gandhinagar, India, November 2, 2017. REUTERS/Amit Dave 

Hindu saints perform rituals to celebrate Akshardham temple's silver jubilee in Gandhinagar, India, November 2, 2017. REUTERS/Amit Dave 

Indian Prime Minister Narendra Modi touches the feet of a saint during Akshardham temple's silver jubilee celebrations in Gandhinagar, India, November 2, 2017. REUTERS/Amit Dave 

Indian Prime Minister Narendra Modi addresses his followers at the Akshardham temple to celebrate the temple's silver jubilee in Gandhinagar, India, November 2, 2017. REUTERS/Amit Dave 

India's Prime Minister Manmohan Singh greets delegates as he attends the silver jubilee celebrations of market regulator Securities and Exchange Board of India (SEBI) in Mumbai May 24, 2013. REUTERS/Danish Siddiqui (INDIA - Tags: POLITICS BUSINESS) 

India's Prime Minister Manmohan Singh attends the silver jubilee celebrations of market regulator Securities and Exchange Board of India (SEBI) in Mumbai May 24, 2013. REUTERS/Danish Siddiqui (INDIA - Tags: POLITICS BUSINESS) 

India's Prime Minister Manmohan Singh greets delegates as he attends the silver jubilee celebrations of market regulator Securities and Exchange Board of India (SEBI) in Mumbai May 24, 2013. REUTERS/Danish Siddiqui (INDIA - Tags: POLITICS BUSINESS) 

Britain's Prince Andrew (L) and Prince Edward pose as they pass a 1977 Silver Jubilee photo of the Royal family on the side of a building, from the deck of the boat 'Havengore' during the Diamond Jubilee pageant on the River Thames in London June 3, 2012. REUTERS/Leon Neal/POOL (BRITAIN - Tags: ROYALS CITYSPACE ENTERTAINMENT) 

A detail of a hat in white Boucle fabric, designed by Angela Kelly, is seen before being worn by Queen Elizabeth at the Diamond Jubilee river pageant in London May 31, 2012. The Boucle has been embroidered with gold, silver and ivory spots and embellished with Swarovski crystals to reflect the River Thames. The outfit is finished with a silk organza frill. The Queen's hat has a swept up brim, the crown of which is made of the same material as the coat and details include feathers hand dyed in Buckingham Palace by one of Angela Kelly's team. Picture taken May 31, 2012 and released June 3, 2012. REUTERS/Lewis Whyld/POOL (BRITAIN - Tags: ROYALS ENTERTAINMENT SOCIETY) 

An ivory dress and coat in white Boucle fabric and threaded throughout with silk ribbon, designed by Angela Kelly, is seen before being worn by Queen Elizabeth at the Diamond Jubilee river pageant in London May 31, 2012. The Boucle has been embroidered with gold, silver and ivory spots and embellished with Swarovski crystals to reflect the River Thames. The outfit is finished with a silk organza frill. Picture taken May 31, 2012 and released June 3, 2012. REUTERS/Lewis Whyld/POOL (BRITAIN - Tags: ROYALS ENTERTAINMENT SOCIETY) 

An ivory dress and coat in white Boucle fabric and threaded throughout with silk ribbon, designed by Angela Kelly, is seen before being worn by Queen Elizabeth at the Diamond Jubilee river pageant in London May 31, 2012. The Boucle has been embroidered with gold, silver and ivory spots and embellished with Swarovski crystals to reflect the River Thames. The outfit is finished with a silk organza frill. The Queen's hat has a swept up brim, the crown of which is made of the same material as the coat and details include feathers hand dyed in Buckingham Palace by one of Angela Kelly's team. Picture taken May 31, 2012 and released June 3, 2012. REUTERS/Lewis Whyld/POOL (BRITAIN - Tags: ROYALS ENTERTAINMENT SOCIETY) 

Original bottle of beers commemorating Britain Queen Elizabeth's silver jubilee are lined up beneath a commemorative plate from 1977 in The Jubilee pub in Sunbury-on-Thames in south west London May 30, 2012. Celebrations to mark Britain's Queen Elizabeth's diamond jubilee begin this weekend. REUTERS/Luke MacGregor (BRITAIN - Tags: ANNIVERSARY SOCIETY ROYALS) 

A press operator polishes a newly struck 60 Crowns coin struck to celebrate the 60th anniversary of the Queen's reign and diamond jubilee and released by the government of the Ascension Islands at the Pobjoy Mint near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver and when completed the crown will be plated gold and set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: ROYALS BUSINESS SOCIETY) 

Press operator John Bower carries a blank coin to be struck as a 60 crowns piece to celebrate the 60th anniversary of Britain's Queen Elizabeth's reign and diamond jubilee released by the government of the Ascension Islands at the Pobjoy Mint near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver and when completed the crown will be plated gold and set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: ROYALS BUSINESS SOCIETY ENTERTAINMENT) 

Press operator John Bower wipes clean a blank coin to be struck as a 60 crowns piece to celebrate the 60th anniversary of Britain's Queen Elizabeth's reign and diamond jubilee released by the government of the Ascension Islands at the Pobjoy Mint near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver and when completed the crown will be plated gold and set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: ROYALS BUSINESS SOCIETY ENTERTAINMENT) 

A press operator John Bower holds a 60 Crowns coin, which reflects the image of Britain's Queen Elizabeth from the coining die mounted in the press above, and was struck to celebrate the 60th anniversary of the Queen's reign and diamond jubilee and released by the government of the Ascension Islands at the Pobjoy Mint near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver and when completed the crown will be plated gold and set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: ROYALS BUSINESS SOCIETY ENTERTAINMENT) 

A press operator holds a 60 Crowns coin, which reflects the image of Britain's Queen Elizabeth from the coining die mounted in the press above, and was struck to celebrate the 60th anniversary of the Queen's reign and diamond jubilee and released by the government of the Ascension Islands at the Pobjoy Mint near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver and when completed the crown will be plated gold and set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: ENTERTAINMENT BUSINESS SOCIETY ROYALS) 

The 60 Crowns coin struck to celebrate the 60th anniversary of Britain's Queen Elizabeth's reign and diamond jubilee released by the government of the Ascension Islands is pictured alongside a Sterling 10 pence piece at the Pobjoy Mint near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver, the crown is plated gold and is set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: ENTERTAINMENT BUSINESS SOCIETY ROYALS) 

Two 60 Crowns coins struck to celebrate the 60th anniversary of Britain's Queen Elizabeth's reign and diamond jubilee released by the government of the Ascension Islands are pictured alongside a Sterling 10 pence piece at the Pobjoy Mint near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver, the crown is plated gold and is set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: ENTERTAINMENT BUSINESS SOCIETY ROYALS) 

A worker at the Ponjoy mint places her hands next to the 60 Crowns coin struck to celebrate the 60th anniversary of Britain's Queen Elizabeth's reign and diamond jubilee, near Reigate in southern England May 30, 2012. The coin is made of 60oz of fine silver, the crown is plated gold and is set with 60 diamonds. The face of the coin has a double effigy of the Queen which is only permitted in a jubilee year. REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS SOCIETY ROYALS ENTERTAINMENT) 

An abseiler secures a giant canvas along the River Thames of a photograph showing Britain's Queen Elizabeth and Royal Family during the 1977 Silver Jubilee, London May 25, 2012. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

An abseiler secures a giant canvas along the River Thames of a photograph showing Britain's Queen Elizabeth and Royal Family during the 1977 Silver Jubilee, London May 25, 2012. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

Abseilers secure a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

Abseilers secure a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

A tourist boat passes a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. A detail of the photograph, shot by an unknown photographer shows (L-R) Louis Mountbatten, Queen Elizabeth and Prince Philip, on the balcony of Buckingham Palace. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

Abseilers secure a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. The photograph, shot by an unknown photographer shows (L-R) Prince Charles, Prince Edward, Prince Andrew, Louis Mountbatten, Queen Elizabeth, Prince Philip, Mark Phillips and Princess Anne on the balcony of Buckingham Palace. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

Abseilers secure a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

Abseilers secure a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

Abseilers secure a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

A tourist boat passes a giant canvas along the River Thames of a photograph showing Britain's Royal Family during the 1977 Silver Jubilee, London May 25, 2012. A detail of the photograph, shot by an unknown photographer shows (L-R) Prince Edward, Prince Andrew, Louis Mountbatten, Queen Elizabeth, Prince Philip, and Mark Phillips, on the balcony of Buckingham Palace. Queen Elizabeth will mark her Diamond Jubilee by travelling in a 1,000-boat regatta on the river on June 3. REUTERS/Suzanne Plunkett (BRITAIN - Tags: ROYALS SOCIETY ENTERTAINMENT) 

India's Prime Minister Manmohan Singh (L) and chief of India's ruling Congress party Sonia Gandhi play a folk drum during the silver jubilee celebrations of the Zonal Cultural Centres (ZCC) at Panchkula in the northern Indian state of Haryana April 13, 2012. REUTERS/Ajay Verma (INDIA - Tags: POLITICS) 

Buddhist guests Desmond Biddulph (L), chairman of the Buddhist Society, Venerable Ajahn Amaro Bhikku and Venerable Bogoda Seelawimala pray after showing Britain's Queen Elizabeth and the Archbishop of Canterbury Rowan Williams (R) a silver Stupa, as they attend a multi-faith reception to mark the Queen's Diamond Jubilee at Lambeth Palace in London February 15, 2012. REUTERS/Matt Dunham/POOL (BRITAIN - Tags: RELIGION ROYALS ENTERTAINMENT SOCIETY) 

Demonstrators protesting the elimination of a popular fuel subsidy that caused the price of petrol to double overnight gather at the Silver Jubilee roundabout in the restive central Nigerian city of Kano, January 4, 2012. Nigerian trade unions on Wednesday called for a national strike and mass demonstrations to shut down oil production and other sectors starting on Monday unless the government restores a fuel subsidy it scrapped this week. REUTERS/Stringer (NIGERIA - Tags: POLITICS CIVIL UNREST BUSINESS) 

Security forces watch demonstrators protesting the elimination of a popular fuel subsidy that caused the price of petrol to double overnight gather at the Silver Jubilee roundabout in the restive central Nigerian city of Kano, January 4, 2012. Nigerian trade unions on Wednesday called for a national strike and mass demonstrations to shut down oil production and other sectors starting on Monday unless the government restores a fuel subsidy it scrapped this week. REUTERS/Stringer (NIGERIA - Tags: POLITICS CIVIL UNREST BUSINESS) 

Demonstrators protesting the elimination of a popular fuel subsidy that caused the price of petrol to double overnight gather at the Silver Jubilee roundabout in the restive central Nigerian city of Kano, January 4, 2012. Nigerian trade unions on Wednesday called for a national strike and mass demonstrations to shut down oil production and other sectors starting on Monday unless the government restores a fuel subsidy it scrapped this week. REUTERS/Stringer (NIGERIA - Tags: POLITICS CIVIL UNREST BUSINESS) 

Onlookers stand beside Indian Air Force (IAF) surface to air missiles on a static display during the silver jubilee celebrations of Vadodara air force station at Harni airfield in Vadodara, about 105 km (65 miles) south of the western Indian city of Ahmedabad September 25, 2009. REUTERS/Amit Dave (INDIA MILITARY) 

Visitors walk beside Sarath BMP II, Mine Protected Vehicles (MPV) and bullet proof cars on display during the silver jubilee celebrations of the ordnance factory at Medak district, about 60 km (37 miles) west of the southern Indian city of Hyderabad July 19, 2009. REUTERS/Krishnendu Halder (INDIA MILITARY ANNIVERSARY) 

Lebanese singer Ragheb Alameh accepts a Silver Jubilee Murex D'or award during the annual Murex d'or award ceremony held in Casino du Liban, north of Beirut June 19, 2009. Picture taken June 19, 2009. REUTERS/Mohamed Azakir (LEBANON ENTERTAINMENT) 

Students perform during a cultural programme on the occasion of the silver jubilee of their school in the northern Indian city of Chandigarh December 19, 2008. Get good grades, stay in school and the sky is the limit, an eastern Indian state government told schoolchildren on Wednesday, promising free glider rides to kids who stay the course. REUTERS/Ajay Verma (INDIA) 

Students perform during a cultural programme on the occasion of the silver jubilee of their school in the northern Indian city of Chandigarh December 19, 2008. Get good grades, stay in school and the sky is the limit, an eastern Indian state government told schoolchildren on Wednesday, promising free glider rides to kids who stay the course. REUTERS/Ajay Verma (INDIA) 

School children shake hands with India's former president A.P.J. Abdul Kalam during a silver jubilee function as part of Children's Day celebrations in the northern Indian city of Chandigarh November 14, 2008. REUTERS/Ajay Verma (INDIA) 

School children shake hands with India's former President A.P.J. Abdul Kalam during a silver jubilee function during Children's Day celebrations in the northern Indian city of Chandigarh November 14, 2008. REUTERS/Ajay Verma (INDIA) 

Kenya's Prime Minister Raila Odinga attends the silver Jubilee lecture of the Nigerian Guardian titled "Democracy and the challenge of Good Governance in Africa" in Lagos, October 9, 2008. REUTERS/Akintunde Akinleye (NIGERIA) 

Coast guard officers march in front of a Dornier aircraft during the aviation silver jubilee celebrations of the Indian coast guard in Daman, about 390 km (242 miles) south from the western Indian city of Ahmedabad May 22, 2007. REUTERS/Amit Dave (INDIA) 

Elephants are being prepared for the World Elephant Polo competition in the Meghuli Forest in south Nepal November 30, 2006. The World Elephant Polo Association is celebrating its 25th silver jubilee year with eight teams representing different countries taking part. BEST QUALITY AVAILABLE REUTERS/Gopal Chitrakar 

A three-month-old baby elephant grabs some food next to its mother at the elephant centre at Meghauli in south Nepal before the World Elephant Polo competition, November 30, 2006. The World Elephant Polo Association is celebrating its 25th silver jubilee year with eight teams representing different countries taking part. REUTERS/Gopal Chitrakar (NEPAL) 

Polo players pet a baby elephant before the World Elephant Polo competition at Meghauli in south Nepal, November 30, 2006. The World Elephant Polo Association is celebrating its 25th silver jubilee year with eight teams representing different countries taking part. REUTERS/Gopal Chitrakar (NEPAL) 

People watch a polo game during the World Elephant Polo competition at Meghuli in south Nepal, November 30, 2006. The World Elephant Polo Association is celebrating its 25th silver jubilee year with eight teams representing different countries taking part. REUTERS/Gopal Chitrakar (NEPAL) 

Elephants are being prepared for the World Elephant Polo competition in the Meghuli Forest in south Nepal November 30, 2006. The World Elephant Polo Association is celebrating its 25th silver jubilee year with eight teams representing different countries taking part. REUTERS/Gopal Chitrakar (NEPAL) Also refer to: GF1DUSDMVOAA 

Elephants cross the Rapti River to take part in the World Elephant Polo competition in the Meghuli Forest in south Nepal November 30, 2006. The World Elephant Polo Association is celebrating its 25th silver jubilee year with eight teams representing different countries taking part. REUTERS/Gopal Chitrakar (NEPAL)