Question: Who is the sibling of the director of Tragedy in the House of Habsburg?

full_context: Document 1: Prince Christoph of Hohenlohe-Langenburg: He died on 6 August 2006 of massive organ failure a few days after being imprisoned in Klong Prem Central Prison in Bangkok on charges of suspicion of illegally altering a visa. His health had been weakened from a weight-loss regimen at a Thai wellness center.
Document 2: María Corda: She began her acting career in the theatres of Budapest in the early days of World War I and soon after the break-up of Austria-Hungary she also began to work in the film industry. Her first role was in "Se ki, se be" in 1919, directed by the Hungarian director, Korda Sandor, who would come to be known as Alexander Korda. She married Sandor, who was then the leading director in Hungary's fledgling film industry, in 1919. He featured her in three films that year "White Rose" ("Fehér rózsa"), "Ave Caesar!" and "Number 111" ("A 111-es") all of which he directed.
Document 3: Yamata: Yamata is a 1919 Hungarian silent drama film directed by Alexander Korda and starring Emil Fenyvessy, Ila Lóth and Gábor Rajnay. The film was made for the state-owned Hungarian film industry during the Hungarian Soviet Republic, and concerns a black slave's revolt against his master. The film's apparent political leftism, along with that of "Ave Caesar!" (1919), led to Korda's arrest once the Soviet Republic collapsed and he fled Hungary in 1919 during the White Terror.
Document 4: Things to Come: Things to Come (also known in promotional material as H. G. Wells' Things to Come) is a 1936 British black-and-white science fiction film from United Artists, produced by Alexander Korda, directed by William Cameron Menzies, and written by H. G. Wells. The film stars Raymond Massey, Ralph Richardson, Cedric Hardwicke, Pearl Argyle, and Margaretta Scott.
Document 5: The Dawn of a Tomorrow (1915 film): The Dawn of a Tomorrow is a 1915 American silent film starring Mary Pickford, produced by Adolph Zukor's Famous Players Film Company and directed by James Kirkwood. It is based on a 1909 stage play starring Eleanor Robson Belmont, her last stage role. This film was rereleased by Paramount in 1919 under their "Success-Series" banner and a copy survives in Sweden today. The story was remade in 1924 again as "The Dawn of a Tomorrow" with Jacqueline Logan in the lead.
Document 6: Tragedy in the House of Habsburg: Tragedy in the House of Habsburg (German: Tragödie im Hause Habsburg) is a 1924 German silent historical film directed by Alexander Korda and starring María Corda, Kálmán Zátony and Emil Fenyvessy. The film recounts the events of the 1889 Mayerling Incident in which the heir to the Austro-Hungarian Empire committed suicide. Studio filming was done in Berlin with location shooting in Vienna. The film cost $80,000 to make, but only earned back around half of this at the box office.
Document 7: Men of Chance: Men of Chance is a 1931 American pre-Code drama film directed by George Archainbaud, starring Ricardo Cortez, Mary Astor, and John Halliday.
Document 8: The Man from Blankley's: The Man from Blankley's is a lost 1930 American pre-Code comedy film, directed by Alfred E. Green. It starred John Barrymore and Loretta Young. The film was based on the 1903 play by Thomas Anstey Guthrie, writing under the pseudonym "F. Anstey". The film was Barrymore's second feature length all-talking film. A previous silent film version of Anstey's play by Paramount Pictures appeared in 1920 as "The Fourteenth Man" starring Robert Warwick. That version is also lost.
Document 9: Men of Tomorrow: Men of Tomorrow is a 1932 British drama film, directed by Zoltan Korda and Leontine Sagan, produced by Alexander Korda and written by Anthony Gibbs and Arthur Wimperis. It stars Maurice Braddell, Joan Gardner and Emlyn Williams and features Robert Donat's movie debut.
Document 10: Tommy Atkins (director): Tommy Atkins was an American director of the silent and early sound film eras. Born on July 18, 1887 in Springfield, Massachusetts, he would make his entrance into the film industry as the assistant director to Ralph Ince on the 1920 silent film, "Out of the Snows". It would be another eight years before he would make another film, again as assistant director, this time for FBO Pictures, on another silent film, "Crooks Can't Win". He'd work as the assistant director on another sixteen films between 1928 and 1934, the most notable of which would be 1933's "Morning Glory", directed by Lowell Sherman and starring Katharine Hepburn and Douglas Fairbanks Jr.. In 1934 he would be given the chance to helm his first picture, "The Silver Streak", which was one of the top money-makers for RKO Pictures that year. He would only direct two more films, the second of which, "Hi, Gaucho!", he would also write the story for.
Document 11: The Daredevil Men: The Daredevil Men is a 1972 British short subject detailing the activities of stunt performers and stunt arrangers featuring Tom Adams.
Document 12: María Corda: María Corda (Mária Antónia Farkas, 4 May 1898 in Déva, Hungary (now Deva, Romania) – 15 February 1976 in Thônex, Switzerland) was a Hungarian actress and a star of the silent film era in Germany and Austria.
Document 13: Alexander Drankov: We know about this period of Drankov’s life from contradictory accounts of his acquaintances. He first tried to make profit by selling jewellery in Kiev, then moved to Yalta and began shooting pornographic films. In November 1920, he emigrated to Constantinople, where he made his living by either organizing cockroach racing events, according to one account, or by film distribution and maintaining an amusement park, according to another account. In 1922, Drankov moved to the United States of America, where he would buy a mobile cinema projector and show films to Russian immigrants. In 1927, he made an attempt to return to film-making business, but his intention to shoot a major film about a love affair between Nicholas II and ballerina Mathilde Kschessinska turned out to be a failure. After his unsuccessful attempt to gain a foothold in Hollywood, Alexander Drankov opened a café in Venice, California, but soon moved to San Francisco, where he would work in his own photo company until his death on 3 January 1949 in San Francisco. He is buried in Colma, California.
Document 14: Men of America: Men of America is a 1932 American Pre-Code Western film directed by Ralph Ince and written by Samuel Ornitz and Jack Jungmeyer. The film stars William Boyd, Charles "Chic" Sale, Dorothy Wilson, Ralph Ince and Henry Armetta. The film was released on November 25, 1932, by RKO Pictures.
Document 15: Crown Prince Rudolph's Last Love: Crown Prince Rudolph's Last Love (German: Kronprinz Rudolfs letzte Liebe/Mayerling) is a 1955 Austrian historical drama film directed by Rudolf Jugert and starring Rudolf Prack, Christiane Hörbiger and Winnie Markus. The film portrays the tragic 1889 Mayerling Incident, in which Rudolf, Crown Prince of Austria and his lover Baroness Mary Vetsera committed suicide.
ground_truth: Zoltan Korda
sub_queries: Who was the director of Tragedy in the House of Habsburg? Answer: Alexander Korda
Alexander Korda >> sibling Answer: Zoltan Korda