Question: Andrea Albert Pierre Casiraghi, is the elder son of Caroline, Princess of Hanover, and her second husband Stefano Casiraghi, and is the eldest grandchild of Rainier III, Prince of Monaco, and which American actress, who became Princess of Monaco after marrying Prince Rainier III, in April 1956?

full_context: Document 1: Andrea Casiraghi: Andrea Albert Pierre Casiraghi (born 8 June 1984) is the elder son of Caroline, Princess of Hanover, and her second husband Stefano Casiraghi. He is the eldest grandchild of Rainier III, Prince of Monaco, and American actress Grace Kelly. Casiraghi is currently fourth in the line of succession to the Monegasque throne, following his twin cousins and mother.
Document 2: Charlotte Casiraghi: Charlotte Marie Pomeline Casiraghi (born 3 August 1986) is the second child of Caroline, Princess of Hanover, and Stefano Casiraghi, an Italian industrialist. She is ninth in line to the throne of Monaco. Her maternal grandparents were Rainier III, Prince of Monaco, and American actress Grace Kelly. She is named after her maternal great-grandmother, Princess Charlotte, Duchess of Valentinois.
Document 3: Rainier III, Prince of Monaco: Rainier III (born Rainier Louis Henri Maxence Bertrand Grimaldi; 31 May 1923 – 6 April 2005) ruled the Principality of Monaco for almost 56 years, making him one of the longest ruling monarchs in European history.
Document 4: Pierre Casiraghi: Pierre Rainier Stefano Casiraghi (born 5 September 1987) is the younger son of Caroline, Princess of Hanover, and her second husband, Stefano Casiraghi. His maternal grandparents were Rainier III, Prince of Monaco, and American actress Grace Kelly. Casiraghi is seventh in the line of succession to the Monegasque throne, following his twin cousins, his mother, brother Andrea, nephew Alexandre, and his niece India Casiraghi.
Document 5: Princess Stéphanie of Monaco: Princess Stéphanie of Monaco, Countess of Polignac (Stéphanie Marie Elisabeth Grimaldi; born 1 February 1965) is the youngest child of Rainier III, Prince of Monaco, and American actress princess Grace of Monaco, and the sister of Albert II, Prince of Monaco, and Caroline, Princess of Hanover. Currently 11th in the line of succession to the Monegasque throne, she has been a singer, swimwear designer and fashion model.
Document 6: Albert II, Prince of Monaco: Albert II (Albert Alexandre Louis Pierre Grimaldi; born 14 March 1958) is the reigning monarch of the Principality of Monaco and head of the princely house of Grimaldi. He is the son of Prince Rainier III and the American actress Grace Kelly. Prince Albert's sisters are Caroline, Princess of Hanover, and Princess Stéphanie. In July 2011, Prince Albert married Charlene Wittstock.
Document 7: Grace Kelly: Grace Patricia Kelly (November 12, 1929September 14, 1982) was an American actress who became Princess of Monaco after marrying Prince Rainier III, in April 1956.
Document 8: Wedding dress of Grace Kelly: The wedding dress of the American actress Grace Kelly, worn during her wedding to Prince Rainer III of Monaco on 19 April 1956, is cited as one of the most elegant and best-remembered bridal gowns of all time, and one of the most famous since the mid 20th century. One author describes the dress as "adding to the marital fervor and elevating matrimonial fashion" and a major influence on women who strove to "emulate Kelly's peau de soie and lace masterpiece". It was designed by Helen Rose of MGM. The dress consisted of a bodice with an attached under-bodice and skirt support. There were two petticoats, one being an attached foundation. The wedding attire included a headdress, veil, shoes and the lace- and pearl-encrusted prayer book which she carried down the aisle. To celebrate the 50th anniversary of the wedding, the Philadelphia Museum of Art (which now owns the dress) displayed it at the museum between 1 April and 21 May 2006 and reported it to have been arguably its most popular exhibit.
Document 9: Elisabeth-Anne de Massy: Elisabeth-Anne de Massy (Noghès) was born in Monaco on 13 January/13 July 1947 to Princess Antoinette of Monaco and her then lover Alexandre-Athenase Noghès. She is a first cousin of the reigning Prince Albert II and niece of Rainier III. She is the godmother of Princess Stéphanie of Monaco. Although Elisabeth-Anne was born out of wedlock, her parents married in 1951, thus legitimizing her, and placing her in line to the throne.
Document 10: Grace Kelly filmography: Grace Kelly (November 12, 1929 – September 14, 1982) was an American actress who made her debut on television in the play "Old Lady Robbins" (1948) on the anthology series, "Kraft Television Theatre". In 1950, she made numerous television appearances on anthology series including "The Philco Television Playhouse", "Studio One", "The Clock", "The Web", and "Danger". The following year, Kelly played Helen Pettigrew in the television play "Berkeley Square" on the "Prudential Family Playhouse". In 1952, she portrayed Dulcinea in the drama "Don Quixote" on the anthology series "CBS Television Workshop". In the same year, Kelly also starred in a number of other anthology series including "Hallmark Hall of Fame", "Lux Video Theatre", and "Suspense".
Document 11: Cary Grant: Cary Grant (born Archibald Alec Leach; January 18, 1904 – November 29, 1986) was a British-American actor, known as one of classic Hollywood's definitive leading men. He began a career in Hollywood in the early 1930s, and became known for his transatlantic accent, debonair demeanor, and light-hearted approach to acting and sense of comic timing. He became an American citizen in 1942.
Document 12: Audrey Hepburn: Audrey Hepburn ( ; born Audrey Kathleen Ruston; May 4, 1929January 20, 1993) was a British actress, model, dancer and humanitarian. Recognized as a film and fashion icon, Hepburn was active during Hollywood's Golden Age. She was ranked by the American Film Institute as the third-greatest female screen legend in Golden Age Hollywood and was inducted into the International Best Dressed List Hall of Fame.
Document 13: Alice Heine: Alice Heine (February 10, 1858 – December 22, 1925), styled HSH The Princess of Monaco, previously The Duchess of Richelieu, was the American-born second wife of Prince Albert I of Monaco, a great-grandfather of Prince Rainier III of Monaco and great-great grandfather of reigning prince Albert II of Monaco. Marcel Proust used her as a model for the "Princesse de Luxembourg" in his novel, "In Search of Lost Time". Her first husband was the Duke of Richelieu, and one of the titles of her second husband was the Duke of Mazarin; she was thus unique in bearing the titles of both Cardinal Richelieu and Cardinal Mazarin.
Document 14: 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 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 of Monaco 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.
Document 15: Prince Rainier Day: Prince Rainier Day is celebrated annually in Monaco on the anniversary of the 19 November 1949 coronation of Rainier III, Prince of Monaco.
ground_truth: Grace Kelly