Prince Charles of Luxembourg
Prince Charles of Luxembourg, Prince of Bourbon- Parma and Nassau( Charles Frédéric Louis Guillaume Marie; 7 August 1927 – 26 July 1977), was a younger son of Grand Duchess Charlotte and Prince Felix of Bourbon- Parma.
Prince Michel of Bourbon-Parma
Prince Michel of Bourbon- Parma
( Michel Marie Xavier Waldemar Georg Robert Karl Eymar; 4 March 1926 – 7 July 2018) was a French businessman, soldier and racing car driver, who was a member of deposed sovereign ducal House of Bourbon- Parma.
He was a son of Prince René of Bourbon- Parma and his wife Princess Margaret of Denmark.
Paternally, he was a grandson of Robert I, Duke of Parma( 1848 – 1907), while through his mother he was a great- grandson of Christian IX of Denmark.
Prince Michel was also the younger brother of Queen Anne of Romania.
Robert, Archduke of Austria-Este
Archduke Robert, Archduke of Austria- Este( 8 February 1915 – 7 February 1996), was the second son of Karl I,( beatified) last Emperor of Austria- Hungary, and Princess Zita of Bourbon- Parma.
Zita of Bourbon-Parma
Zita of Bourbon-Parma ("Zita Maria delle Grazie Adelgonda Micaela Raffaela Gabriella Giuseppina Antonia Luisa Agnese"; 9 May 1892 – 14 March 1989) was the wife of Charles, the last monarch of Austria-Hungary.
As such, she was the last Empress of Austria and Queen of Hungary, in addition to other titles.
Born as the seventeenth child of the dispossessed Robert I, Duke of Parma, and his second wife, Infanta Maria Antonia of Portugal, Zita married the then Archduke Charles of Austria in 1911.
Charles became heir presumptive to the Emperor Franz Joseph
I of Austria in 1914 after the assassination of his uncle Archduke Franz Ferdinand of Austria, and acceded to the throne in 1916 after the old emperor's death.
After the end of World War I in 1918, the Habsburgs were deposed and the empire became four independent countries, Austria, Hungary, and the newly formed Czechoslovakia and State of Slovenes, Croats and Serbs.
Charles and Zita left for exile in Switzerland and were subsequently removed from Hungary by the Allies to Madeira, where Charles died in 1922.
After her husband's death, Zita and her son Otto served as symbols of unity for the exiled dynasty.
A devout Catholic, she raised a large family after being widowed at the age of 29, and never remarried.
Archduchess Elisabeth of Austria (1922–1993)
Archduchess Elisabeth of Austria( 31 May 1922 – 6 January 1993) was a member of the House of Habsburg- Lorraine.
She was the youngest daughter of Charles I, the last Emperor of Austria, and his wife, Princess Zita of Bourbon- Parma.
Princess Carolina, Marchioness of Sala
Princess Maria" Carolina" Christina of Bourbon- Parma, Marchioness of Sala( born 23 June 1974), is the fourth and youngest child of Princess Irene of the Netherlands and Carlos Hugo, Duke of Parma, and is a member of the Royal and Ducal House of Bourbon- Parma, as well as of the Dutch Royal Family.
Archduchess Charlotte of Austria
Archduchess Charlotte of Austria
( 1 March 1921 – 23 July 1989) was a daughter of Emperor Charles I of Austria and his wife Princess Zita of Bourbon- Parma.
She was also known by the name Charlotte de Bar while a welfare worker in the United States of America from 1943 to 1956.
Infanta Maria Antonia of Portugal
Infanta Maria Antónia of Portugal
(Portuguese: "Maria Antónia
Adelaide Camila Carolina Eulália
Leopoldina Sofia Inês Francisca de Assis e de Paula Micaela Rafaela Gabriela Gonzaga Gregória Bernardina Benedita Andrea"
; 28 November 1862 – 14 May 1959) was a Portuguese infanta, the seventh and last child of Miguel of Portugal and
Adelaide of Löwenstein-Wertheim-Rosenberg.
Princess Margarita, Countess of Colorno
Princess Margarita Maria Beatriz of Bourbon-Parma, Countess of Colorno (born 13 October 1972), is the eldest daughter of Princess Irene of the Netherlands and Carlos Hugo, Duke of Parma, and is member of the Royal and Ducal House of Bourbon-Parma, as well of the Dutch Royal Family.
Archduke Rudolf of Austria (1919–2010)
Archduke Rudolf of Austria (5 September 1919 – 15 May 2010) was the sixth child and youngest son of Emperor Charles I of Austria and Zita of Bourbon-Parma.

Question: Who is the maternal grandmother of Zita Of Bourbon-Parma?
Answer: Adelaide of Löwenstein-Wertheim-Rosenberg