As King Charles battles on with his cancer diagnosis, it is said the reigning monarch has adopted one of Prince Philip's most defining traits - his no-nonsense attitude. A man of action rather ...

"It is with deep sorrow that Her Majesty The Queen announces the death of her beloved husband," Buckingham Palace said in a statement Friday Simon Perry is a writer and correspondent at PEOPLE.

Prince Philip's cause of death has been revealed. The Duke of Edinburgh, who died on April 9 at the age of 99, died of "old age," according to a death certificate obtained by The Telegraph.