There will be heartbreak for King Charles and Prince William as the pair learned of the death of King Constantine II, the last monarch of Greece.
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Constantine's first cousin was Prince Philip, making King Charles his second cousin. The pair were very close and Charles even named Constantine as William's godfather. William himself would go on to be named godfather of Constantine's first grandson, Constantine Alexios.
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The former Greek monarch passed away on Tuesday with his wife and children by his side, with sister Queen Sofia and Princess Irene flying back to Greece to be with their family member.
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Constantine, who was 82 when he passed away, had been suffering from ill health for a number of years and was being treated at the private Hygeia Hospital in Athens.
An official statement from his office on Wednesday read: "It is with deep sadness that the Royal Family announces that HM King Constantine, beloved husband, father, and brother, passed away yesterday, January 10, 2023, while being treated at ‘HYGEIA’ hospital in Greece. Details will follow regarding his funeral procession and burial."
There had been concerns over the royal's recent health after he was unable to attend the funeral of Queen Elizabeth II, with his wife and two of their children attending in his place.
Constantine passed away on Tuesday
Constantine acceded to the Greek throne in 1964 following the death of his father, King Paul. However, he would rule for less than a decade after a military junta abolished the monarchy.
Two referendums were held following the abolition, a disputed one in 1973 before a second one in 1974, with both returning results in favour of abolition.
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The father-of-three lived in exile for many years in Hampstead Garden Suburb, before eventually returning to his native country in 2010.
Alongside being a royal, he was also an accomplished sportsman, and even won a gold medal in the 1960 Olympics in the sailing.
He leaves behind his wife, Queen Anne-Marie and five children: Princess Alexia, Crown Prince Pavlos, Prince Nikolaos, Princess Theodora and Prince Philippos.