Ogawa Mataji
Viscount was a general in the early Imperial Japanese Army.
He was also the father- in- law of Field Marshal Gen Sugiyama.
Ludwig von Westphalen
Johann Ludwig von Westphalen( 11 July 1770 – 3 March 1842) was a liberal Prussian civil servant and the father- in- law of Karl Marx.
Harry Smith (athlete)
Harry James Smith( July 30, 1888 – November 20, 1962) was an American long- distance runner.
He was most notable for competing in the 1912 Olympics in Stockholm.
He was also the father of Hart wrestling family matriarch Helen Hart and the father- in- law of Stu Hart.
Philip Niarchos
Philip Niarchos (alternately: Philippos or Philippe) (born 1954) is a Greek billionaire, the eldest son of the Greek shipping magnate Stavros Niarchos and Eugenia Livanos, herself the elder daughter of Stavros Niarchos' rival Stavros G. Livanos.
John Vernou Bouvier III
John Vernou" Black Jack" Bouvier III( May 19, 1891 – August 3, 1957) was an American Wall Street stockbroker and socialite.
He was the father of First Lady Jacqueline Kennedy Onassis and of socialite Lee Radziwill, and was the father- in- law of John F. Kennedy.
Victoria Niarchos
Victoria Christina Niarchos (née Guinness, born 30 January 1960) is a member of the banking branch of the Guinness beer clan.
She is a daughter of "Patrick" Benjamin Guinness (1931-1965) (himself half-brother of the Aga Khan IV) and his wife (and stepsister), the former Dolores Guinness, "Dolores" Maria Agatha Wilhelmine Luise, Freiin von Fürstenberg-Hedringen (1936-2012), herself the daughter of the Mexican socialite Gloria Guinness (1912-1980) and Count Franz-Egon von Fürstenberg-Herdringen (1896-1975).
She has two older siblings:
Countess Maria Alexandra de Quatrebarbes born (b. 1956) and Loel Patrick Guinness (b. 1957).
The third and former wife of Greek shipping heir Philip Niarchos (b. 1954), she is the mother of:
John Adams (merchant)
John Adams( 1672 or 1673 – 1745) was an American- born Canadian merchant and member of the Nova Scotia Council.
He was the father- in- law of Henry Newton( politician).
Barthold A. Butenschøn Sr.
Hans Barthold Andresen Butenschøn( 27 December 1877 – 28 November 1971) was a Norwegian businessperson.
He was born in Kristiania as a son of Nils August Andresen Butenschøn and Hanna Butenschøn, and grandson of Nicolay Andresen.
Together with Mabel Anette Plahte( 1877 – 1973, a daughter of Frithjof M. Plahte) he had the son Hans Barthold Andresen Butenschøn Jr. and was through him the father- in- law of Ragnhild Butenschøn and grandfather of Peter Butenschøn.
Through his daughter Marie Claudine he was the father- in- law of Joakim Lehmkuhl, through his daughter Mabel Anette he was the father- in- law of Harald Astrup( a son of Sigurd Astrup) and through his daughter Nini Augusta he was the father- in- law of Ernst Torp.
He took commerce school and agricultural school.
He was hired in the family company N. A. Andresen& Co, and became a co-owner in 1910.
He eventually became chief executive officer.
The bank changed its name to Andresens Bank in 1913 and merged with Bergens Kreditbank in 1920.
The merger was dissolved later in the 1920s.
He was also a landowner, owning Nedre Skøyen farm and a lot of land in Enebakk.
He chaired the board of Nydalens Compagnie from 1926, having not been a board member before that.
He also chaired the supervisory council of Forsikringsselskapet Viking and Nedre Glommen salgsforening, and was a supervisory council member of Filharmonisk Selskap.
He was a member of the gentlemen's club SK Fram since 1890, and was proclaimed a lifetime member in 1964.
He was buried in Enebakk.
Peter Burroughs
Peter Burroughs( born 27 January 1947) is a British television and film actor, the director of Willow Management.
He is the father- in- law of actor and TV presenter Warwick Davis.
James Armour (Master mason)
James Armour (15 January 1730 – 20 September 1798) was a master mason and father of Jean Armour, and therefore the father-in-law of the poet Robert Burns.

Question: Who is the father-in-law of Victoria Niarchos?
Answer: Stavros Niarchos