Michael Asen IV of Bulgaria
Michail Asen  (c. 1322–1355) was the eldest son of Ivan Alexander of Bulgaria from his marriage with Theodora of Wallachia.
After his father acceded to the throne in 1331, the young prince was proclaimed co-Emperor.
He was to succeed his father under the name Michael IV Asen.
The heir to the throne was the pride of the royal family and was said to possess "all virtues".
He married Maria, renamed Irina, the daughter of Andronikos III Palaiologos.
In 1354–1355 the Ottoman Turks invaded Bulgaria and headed towards Plovdiv and Sofia.
It is mentioned in an anonymous Bulgarian chronicle that Michail Asen gathered the Bulgarians and engaged the Turks near Sofia.
The Bulgarians were defeated and suffered heavy casualties including Michail himself.
But the battle was not in vain: the Ottomans failed to capture the cities and did not attack the country up to 1370.In
the Bulgarian folklore is mentioned that the son of the Emperor perished with the death of the brave.
Maria-Irene Palaiologina
Irene Palaiologina (Irina; Ειρήνη Παλαιολογίνα) (1327 - after 1356) was a Byzantine princess and Bulgarian empress consort.
She was also known as Maria Palaiologina (Μαρία Παλαιολογίνα).
Her parents were Andronikos III Palaiologos and Anna of Savoy, whilst her siblings were John V Palaiologos and Michael Palaiologos.
She married in 1336 Tsar Michael Asen IV of Bulgaria.
Nothing else is known about her, except that she was an Orthodox Christian.
Irene Palaiologina (Byzantine empress)
Irene Palaiologina( died after 1356), was the Empress consort of Matthew Kantakouzenos.
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.
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.
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.
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.
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.

Question: Who is Maria-Irene Palaiologina's mother-in-law?
Answer: Theodora of Wallachia