Prince Alfonso, Count of Caserta
Prince "Alfonso", Count of Caserta (28 March 1841 – 26 May 1934) was the third son of Ferdinand II of the Two Sicilies and Archduchess Maria Theresa of Austria.
He was pretender to the throne of the Two Sicilies in succession of his older half-brother, Francis II of the Two Sicilies.
He was succeeded by his eldest son, Ferdinand Pius.
Princess Urraca of Bourbon-Two Sicilies
Princess Urraca of Bourbon- Two Sicilies( July 14, 1913, Nymphenburg Palace, Munich, Kingdom of Bavaria – May 3, 1999, Sigmaringen, Baden- Württemberg, Germany) was a member of the House of Bourbon- Two Sicilies and a Princess of Bourbon- Two Sicilies.
Maria Carolina Zamoyska
Princess Maria Carolina of Bourbon- Two Sicilies, Duchess of Castro( née Countess Maria Carolina Zamoyska)( 22 September 1896 in Kraków, Austria- Hungary – 9 May 1968 in Marseille, France) was the wife of Prince Ranieri, Duke of Castro, claimant to the headship of the House of Bourbon- Two Sicilies.
Carolina was the sixth child and youngest daughter of Polish nobleman Andrzej Przemysław Zamoyski, Count Zamoyski and his wife Princess Maria Carolina of Bourbon- Two Sicilies.
Carolina's maternal grandparents were Prince Francis of Bourbon- Two Sicilies, Count of Trapani and his wife Archduchess Maria Isabella of Austria, Princess of Tuscany.
Princess Maria Antonietta of Bourbon-Two Sicilies
Princess Maria Antonietta of Bourbon-Two Sicilies (Maria Antonietta Giuseppina Leopoldina; 16 March 1851 – 12 September 1938) was a Princess of Bourbon-Two Sicilies by birth and by her marriage to Prince Alfonso, Count of Caserta, claimant to the defunct throne of the Two Sicilies.
Duchess Elisabeth of Württemberg (b. 1933)
Duchess Elisabeth of Württemberg( born 2 February 1933) is a member of the House of Württemberg and a Duchess of Württemberg by birth and through her marriage to Prince Antoine of Bourbon- Two Sicilies, a member of the House of Bourbon- Two Sicilies and a Princess of Bourbon- Two Sicilies.
Prince Carlos of Bourbon-Two Sicilies
Don Carlos, Prince of Bourbon- Two Sicilies, Infante of Spain( Full Italian name:" Carlo Maria Francesco d' Assisi Pasquale Ferdinando Antonio di Padova Francesco de Paola Alfonso Andrea Avelino Tancredi, Principe di Borbone delle Due Sicilie, Infante di Spagna"; 10 November 1870,, Bolzano, Austria- Hungary – 11 November 1949, Seville, Spain) was the son of Prince Alfonso of the Two Sicilies, Count of Caserta and his wife Princess Maria Antonietta of Bourbon- Two Sicilies, and nephew of the last King of the Two Sicilies, Francis II.
Prince Philip of Bourbon-Two Sicilies
Prince Philip of Bourbon- Two Sicilies( Filippo Maria Alfonso Antonio Ferdinando Francesco di Paola Lodovico Enrico Alberto Taddeo Francesco Saverio Uberto; 10 December 1885 – 9 March 1949) was a member of the House of Bourbon- Two Sicilies and a Prince of Bourbon- Two Sicilies.
Leopold, Prince of Salerno
Leopoldo Giovanni Giuseppe Michele of Bourbon- Two Sicilies, Prince of Salerno( 2 July 1790, Naples, Kingdom of Naples – 10 March 1851, Naples, Kingdom of the Two Sicilies) was a member of the House of Bourbon- Two Sicilies and a Prince of Bourbon- Two Sicilies.
Princess Maria Immaculata of Bourbon-Two Sicilies (1874–1947)
Princess" Maria Immaculata" Cristina Pia Isabella of Bourbon- Two Sicilies( Full Italian name:" Maria Immacolata Speranza Pia Teresa Cristina Filomena Lucia Anna Isabella Cecilia Apollonia Barbara Agnese Zenobia, Principessa di Borbone delle Due Sicilie")( 30 October 1874 – 28 November 1947) was the fourth child and eldest daughter of Prince Alfonso of Bourbon- Two Sicilies, Count of Caserta and his wife Princess Maria Antonietta of Bourbon- Two Sicilies.
Prince Carlo, Duke of Castro
Prince Carlo of Bourbon- Two Sicilies, Duke of Castro( born 24 February 1963) is a claimant to the headship of the House of Bourbon- Two Sicilies.

Question: Who is Princess Maria Antonietta Of Bourbon-Two Sicilies's father-in-law?
Answer: Ferdinand II of the Two Sicilies