Question: When was the older sister of Princess Benedikte of Denmark born?
Related documents: [0]  [DOC] Margrethe II (Danish: "Margrethe 2." , ] ; Faroese: "Margreta 2." ; Greenlandic: "Margrethe II" ; full name: "Margrethe Alexandrine Þórhildur Ingrid"; born 16 April 1940) is the Queen of Denmark. She is also the supreme authority of the Church of Denmark and Commander-in-Chief of the Danish Defence. Born into the House of Glücksburg, a royal house with origins in Northern Germany, she was the eldest child of Frederick IX of Denmark and Ingrid of Sweden. She succeeded her father upon his death on 14 January 1972, having had become heir presumptive to her father in 1953, when a constitutional amendment allowed women to inherit the throne. On her accession, Margrethe became the first female monarch of Denmark since Margaret I, ruler of the Scandinavian kingdoms in 1375–1412 during the Kalmar Union. In 1967, she married Henri de Laborde de Monpezat, with whom she has two sons: Crown Prince Frederik (born 1968) and Prince Joachim (born 1969). She has been on the Danish throne for 45 years, becoming the second-longest-reigning Danish monarch after her ancestor Christian IV. [END] 
[1]  [DOC] Princess Benedikte of Denmark, Princess of Sayn-Wittgenstein-Berleburg {'1': ", '2': ", '3': 'RE, SKmd, D.Ht.', '4': "} (Benedikte Astrid Ingeborg Ingrid, born 29 April 1944) is the second daughter of King Frederick IX of Denmark and Ingrid of Sweden. She is the younger sister of the reigning Queen of Denmark, Margrethe II, and the older sister of Queen Anne-Marie of Greece. [END] 
Answer: 
16 April 1940
16 April 1940