Caroline, Princess of Hanover Caroline, Princess of Hanover Caroline, Princess of Hanover (Caroline Louise Marguerite Grimaldi; born 23 January 1957), is the eldest child of Rainier III, Prince of Monaco, and the American actress Grace Kelly. She is the elder sister of Prince Albert II and Princess Stéphanie. Until the births of her niece and nephew, Princess Gabriella and Prince Jacques, in December 2014 she had been heir presumptive to the throne of Monaco since 2005, a position which she previously held from 1957 to 1958. Caroline is married to Ernst August, Prince of Hanover (born 1954), the heir to the former throne of
Charles III, Prince of Monaco Charles III, Prince of Monaco Charles III (8 December 1818 – 10 September 1889) was Prince of Monaco and Duke of Valentinois from 20 June 1856 to his death. He was the founder of the famous casino in Monte Carlo, as his title in Monegasque and Italian was Carlo III. He was born in Paris Charles Honoré Grimaldi, the only son of Florestan I of Monaco and Maria Caroline Gibert de Lametz. While he was Hereditary Prince, Charles was married on 28 September 1846 in Brussels to Countess Antoinette de Mérode-Westerloo. He succeeded his father Prince Florestan I in 1856.