Princess Caroline of Hanover, left, takes part with her son Andrea Casiraghi with his wife Tatiana and their son Sacha, to the celebration of the 10th anniversary of the accession to the throne of his brother Prince Albert II, Saturday, July 11, 2015, in Monaco. On 31 March 2005, the Palace of Monaco announced that Hereditary Prince Albert would take over the duties of his father as regent since Rainier was no longer able to exercise his functions as sovereign. On 6 April 2005, Prince Rainier III died and Hereditary Prince Albert became Albert II, Sovereign Prince of Monaco. REUTERS/Lionel Cironneau/Pool