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.
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.
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.
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.
Ferdinand I of the Two Sicilies
Ferdinand I (12 January 1751 – 4 January 1825), was the King of the Two Sicilies from 1816, after his restoration following victory in the Napoleonic Wars.
Before that he had been, since 1759, Ferdinand IV of the Kingdom of Naples and Ferdinand III of the Kingdom of Sicily.
He was also King of Gozo.
He was deposed twice from the throne of Naples: once by the revolutionary Parthenopean Republic for six months in 1799 and again by Napoleon Bonaparte in 1805.
Ferdinand was the third son of King Charles VII of Naples and V of Sicily by his wife, Maria Amalia of Saxony.
On 10 August 1759, Charles succeeded his elder brother, Ferdinand VI, becoming King Charles III of Spain, but treaty provisions made him ineligible to hold all three crowns.
On 6 October, he abdicated his Neapolitan and Sicilian titles in favour of his third son, because his eldest son Philip had been excluded from succession due to illnesses and his second son Charles was heir to the Spanish throne.
Ferdinand was the founder of the cadet House of Bourbon-Two Sicilies.
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.
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.
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.
Lucia Migliaccio
Lucia Migliaccio, Duchess of Floridia (19 July 1770, in Syracuse, Sicily – 26 April 1826, in Naples) was the second wife of Ferdinand I of the Two Sicilies.
Their marriage was morganatic and Lucia was never a Queen consort.

Question: Who is Lucia Migliaccio's mother-in-law?
Answer: Maria Amalia of Saxony