Question: Who is the spouse of the star of the film Sleeping Fires?

full_context: Document 1: The Woman on the Index: The Woman on the Index is a lost 1919 American silent drama film directed by Hobart Henley and starring Pauline Frederick and her then husband playwright Willard Mack. It was Frederick's first film at Goldwyn Pictures after coming over from Paramount. It is based on a 1918 Broadway play, "The Woman on the Index", that starred Julia Dean.
Document 2: The Unchastened Woman: The Unchastened Woman is a 1925 American silent drama film starring vamp Theda Bara, directed by James Young, the former husband of Clara Kimball Young, and released by start-up studio Chadwick Pictures. The film is based on a 1915 Broadway play, "The Unchastened Woman", which starred Emily Stevens.
Document 3: The Soul of Broadway: The Soul of Broadway is a 1915 American silent crime drama film produced and distributed by the Fox Film Corporation and directed by Herbert Brenon. Popular vaudeville performer Valeska Suratt starred in the film which was also her silent screen debut. "The Soul of Broadway" is now considered lost. It is one of many silent films that were destroyed in a fire at Fox's film storage facility in Little Ferry, New Jersey in July 1937.
Document 4: A Woman of Pleasure: A Woman of Pleasure is a lost 1919 American silent drama film directed by Wallace Worsley and starring Blanche Sweet. It was distributed by Pathé Exchange in the United States.
Document 5: Thieves' Gold: Thieves' Gold is a 1918 American Western film directed by John Ford and featuring Harry Carey. It is considered to be a lost film.
Document 6: Sleeping Fires: Sleeping Fires was a 1917 American silent drama film directed by Hugh Ford, and starring Pauline Frederick. The film is now considered lost.
Document 7: The Branded Woman: The Branded Woman is a 1920 American silent drama film released by First National Pictures. It stars Norma Talmadge who also produced the film along with her husband Joseph Schenck through their production company, Norma Talmadge Productions. The film is based on a 1917 Broadway play "Branded", by Oliver D. Bailey and was adapted for the screen by Anita Loos and Albert Parker who also directed.
Document 8: A Daughter of the Old South: A Daughter of the Old South is a lost 1918 American drama silent film directed by Émile Chautard and written by Alicia Ramsey, Rudolph de Cordova and Margaret Turnbull. The film stars Pauline Frederick, Pedro de Cordoba, Vera Beresford, Rex McDougall, Mrs. T. Randolph and Myra Brooks. The film was released on November 24, 1918, by Paramount Pictures.
Document 9: Jack Standing: The son of stage actor Herbert Standing and brother of Wyndham Standing (1880–1963), who also was a famous actor in the early days of film, Jack Standing first appeared in Broadway musicals such as "The Belle of New York" and "Florodora" before he went to the Biograph Company in 1909. Because he was a handsome young man, he was quickly offered many roles and signed a contract with Sigmund Lubin in 1911. Like many others from the silent film, Standing was asked to play quite everything from passionate lovers to villains or old men. In 1915, he told the "Moving Picture World" magazine, "Spare me from being a one-type actor!" He appeared in more than fifty films. An incomplete print of 1915 Mary Pickford vehicle "Fanchon the Cricket", in which Standing co-starred, has recently been found. The teenage Fred and Adele Astaire allegedly made their screen debuts in this film. Standing's greatest success was the 1916 film "Hell's Hinges", where he played the weak-willed brother of Clara Williams.
Document 10: The Red Widow: The Red Widow is a lost 1916 silent comedy film produced by Famous Players-Lasky, distributed by Paramount Pictures. The film was based on a 1911 Broadway musical play "The Red Widow" by Channing Pollock and Rennold Wolf and starring comedian Raymond Hitchcock. John Barrymore stars in this film in the Hitchcock part of Cicero Butts. Hitchcock's wife, Flora Zabelle, is the leading lady in this film.
Document 11: The Silent Lie: The Silent Lie is a 1917 silent drama film, produced and released by Fox Film Corporation, directed by Raoul Walsh, and starring Walsh's then-wife Miriam Cooper.
Document 12: Our Mrs. McChesney: Our Mrs. McChesney is a lost 1918 American silent comedy drama film produced and distributed by Metro Pictures, directed by Ralph Ince, and based on the 1915 play by Edna Ferber and George Hobart which starred Ethel Barrymore.
Document 13: Woman (1918 film): Woman is a 1918 American silent film directed by Maurice Tourneur, an allegorical film showcasing the story of women through points in time. Popular in its day, the film was distributed in the State's Rights plan as opposed to a major distributor like Paramount or Universal. This film has been preserved in private collections and in major venues like the Museum of Modern Art and reportedly the Gosfilmofond Archive in Russia.
Document 14: The Trail of Hate (1917 film): The Trail of Hate is a 1917 American short drama film directed by John Ford. The film is now considered to be lost.
Document 15: Sure Fire: Sure Fire is a 1921 American Western film directed by John Ford and featuring Hoot Gibson. It is considered to be a lost film.
ground_truth: Willard Mack
sub_queries: In the film Sleeping Fires, who was the star? Answer: Pauline Frederick
Pauline Frederick >> spouse Answer: Willard Mack