Infante Alfonso, Duke of Calabria
Infante Alfonso of Spain, Prince of the Two Sicilies, Duke of Calabria (30 November 1901 – 3 February 1964) was one of two claimants to the title of the head of the House of Bourbon-Two Sicilies from 1960 until his death in 1964.
Alfonso was the son of Prince Carlos of Bourbon-Two Sicilies (1870–1949) and his wife, Mercedes, Princess of Asturias (1880–1904).
He was born and died in Madrid, Spain.
Alfonso's mother was Mercedes, Princess of Asturias, but she died in childbirth in 1904.
King Alfonso XIII of Spain was unmarried at the time so as the Princess of the Asturias' eldest son, Alfonso became heir-presumptive to the Spanish crown, though, unlike his mother, he never held the title of Prince of Asturias.
He was heir-presumptive until the birth of his cousin, Alfonso in 1907, to Alfonso XIII and Queen Victoria Eugenie.
Infanta Alicia, Duchess of Calabria
Infanta Alicia of Spain, Duchess of Calabria (née: "
Princess Alicia Maria Teresa Francesca Luisa Pia Anna Valeria of Bourbon-Parma"; 13 November 1917 – 28 March 2017) was a daughter of Elias, Duke of Parma, and Archduchess Maria Anna of Austria.
Alicia was Duchess of Calabria through her marriage to Infante Alfonso, Duke of Calabria (1901–1964).
She bore the title of Infanta of Spain from 1936, and took part in some of the activities that the Spanish Royal Family organises.
Through marriage, she was maternal half-aunt of Juan Carlos I of Spain.
She was born in Vienna, Austria-Hungary, and died in Madrid, Spain.
She was paternal first cousin of Boris III of Bulgaria, and paternal half-first cousin of Jean, Grand Duke of Luxembourg, Otto, Crown Prince of Austria and Queen Anne of Romania.
Marian Shields Robinson
Marian Lois Robinson( née Shields; born July 29, 1937) is the mother of Michelle Obama, former First Lady of the United States, and Craig Robinson, a basketball executive, and the mother- in- law of former U.S. President Barack Obama.
Donna Harun
Donna Harun( born February 21, 1968) is an Indonesian actress and model of Dutch- Indonesian descent.
She is the mother of actor Ricky Harun and mother- in- law of the actress and model Herfiza Novianti.
Vera Miletić
Vera Miletić (Serbian Cyrillic: Вера Милетић; 8 March 1920 – 7 September 1944) was a Serbian student and soldier.
She was notable for being the mother of Mira Marković, posthumously making her the mother-in-law of Serbian president Slobodan Milošević.
Baroness Gösta von dem Bussche-Haddenhausen
Baroness Gösta von dem Bussche- Haddenhausen( 26 January 1902 – 13 June 1996) was the mother of Prince Claus of the Netherlands, who was the Prince Consort of Queen Beatrix of the Netherlands, thus making her the mother- in- law of the former Dutch Queen.
She is also the paternal grandmother of King Willem- Alexander of the Netherlands, who is the current Dutch King.
Maria Thins
Maria Thins( c. 1593 – 27 December 1680) was the mother- in- law of Johannes Vermeer and a member of the Gouda Thins family.
Priscilla Pointer
Priscilla Marie Pointer( born May 18, 1924) is an American stage, film and television character actress.
She began her career in the theater, including productions on Broadway.
Later, Pointer moved to Hollywood to act in films and on television.
She is the mother of Amy Irving, therefore making her the former mother- in- law of filmmakers Steven Spielberg and Bruno Barreto and the mother- in- law of documentary filmmaker Kenneth Bowser, Jr.
Eldon Howard
Eldon Howard was a British screenwriter.
She was the mother- in- law of Edward J. Danziger and wrote a number of the screenplays for films by his company Danziger Productions.
Doria Ragland
Doria L. Ragland( born September 2, 1956) is the mother of Meghan, Duchess of Sussex, the mother- in- law of Prince Harry, and the maternal grandmother of Archie Mountbatten- Windsor, who is seventh in line to the British throne.
She is a former makeup artist, business owner, yoga instructor, and former social worker who worked in the mental health sector from 2015 to 2018.

Question: Who is the mother-in-law of Infanta Alicia, Duchess Of Calabria?
Answer: Mercedes, Princess of Asturias