Princess Marie Louise of Bulgaria
Princess Maria Louise of Bulgaria (born 13 January 1933, Sofia) is the daughter of Tsar Boris III and Tsaritsa Ioanna and the older sister of Simeon II of Bulgaria.
Her baptism in the Bulgarian Orthodox Church caused controversy at the time.
Andreas, Prince of Leiningen
Andreas, Prince of Leiningen ("Andreas Fürst zu Leiningen"; born 27 November 1955) is the current head of the Princely House of Leiningen.
He is the son of Emich Kyrill, Prince of Leiningen, and Duchess Eilika of Oldenburg.
His older brother Prince Karl Emich of Leiningen lost his rights to succeed as head of the house as a result of his unequal second marriage.
His paternal grandmother, Grand Duchess Maria Kirillovna of Russia, was the eldest daughter of Kirill Vladimirovich, Grand Duke of Russia (first claimant to the throne of Russia and a grandson of Alexander II of Russia) and Princess Victoria Melita of Edinburgh (granddaughter of Alexander II of Russia).
Because of this, he is in the line of succession to the former Russian throne.
His great-great-great grandfather, Carl Friedrich Wilhelm Emich, 3rd Prince of Leiningen, was the elder half-brother of Queen Victoria.
Through his father, he is also a direct descendant (specifically a great-great-great-grandson) of Queen Victoria, through her granddaughter, Princess Victoria Melita of Edinburgh, whose second husband was Grand Duke Kirill Vladimirovich.
Because of this, he is in the line of succession to the British Throne.
He married Princess Alexandra of Hanover on 5 October 1981.
They have three children:
Agnes of Leiningen
Agnes of Leiningen( died after December 1299) was a countess of the House of Leiningen and by marriage Countess of Nassau.
She was probably Regent of the County of Nassau for some time for her youngest son.
Karl, Prince of Leiningen
Karl, Prince of Leiningen( 13 February 18982 August 1946) was the son of Emich, 5th Prince of Leiningen.
He was the 6th Prince of Leiningen from 1939 until his death.
Princess Margarita of Leiningen
Princess Margarita of Leiningen( Full German name:" Margarita Ileana Viktoria Alexandra Prinzessin zu Leiningen")( born 9 May 1932 in Coburg, Bavaria, Germany; committed suicide on 16 June 1994 in Überlingen, Baden- Württemberg, Germany) was a Princess of Leiningen by birth and the Princess of Hohenzollern by marriage.
Margarita was the fourth child and second- eldest daughter of Karl, 6th Prince of Leiningen and his wife Grand Duchess Maria Kirillovna of Russia.
Margarita was the Princess consort of Hohenzollern 6 February 1966 – 16 June 1994.
Emich, 5th Prince of Leiningen
Emich, 5th Prince of Leiningen( 18 January 1866 – 18 July 1939) was the son of Ernst Leopold, 4th Prince of Leiningen.
He was 5th Prince of Leiningen from 1904 to 1918, and afterwards titular Prince of Leiningen from 1918 until his death.
Minamoto no Chikako
She was the mother of Prince Morinaga.
Prince Karl Emich of Leiningen
Prince Karl Emich of Leiningen( born 12 June 1952), also known by his Orthodox Russian name Nikolai Kirillovich Romanov( Никола́й Кири́ллович Рома́нов) and his pretended regnal name Emperor Nicholas III, is the eldest son of Emich, 7th Prince of Leiningen and his wife, Duchess Eilika of Oldenburg, and is an elder brother of Andreas, 8th Prince of Leiningen.
He is a claimant to the defunct throne of the Russian Empire, held until 1917 by the Imperial House of Romanov, as a grandson of Grand Duchess Maria Kirillovna( 1907 – 1951), eldest child of Grand Duke Kirill Vladimirovich, who claimed the Russian crown from exile in 1924.
He is a great- great- grandson of Emperor Alexander II of Russia and grand nephew of Grand Duke Vladimir Kirillovich of Russia.
In 2013, the Monarchist Party of Russia declared him the primary heir to the Russian throne upon his conversion from Lutheranism to Eastern Orthodox Christianity, and in 2014 announced the formation of the" Imperial Throne", wherein Karl Emich had agreed to assume imperial dignity as" Emperor Nicholas III".
He also claimed the throne of Leiningen in the past.
Prince Boris of Leiningen
Prince Karl "Boris" Frank Markwart of Leiningen (born 17 April 1960) is the elder son of Prince Karl of Leiningen and of his wife, Princess Marie Louise of Bulgaria.
As a third great-grandson of Queen Victoria, he is in the line of succession to the throne of Canada and those of the other Commonwealth realms.
Alexandra, Princess of Leiningen
Princess Alexandra of Hanover, Duchess of Brunswick- Lüneburg, Princess of Leiningen( born 18 February 1959), is the wife of Andreas, 8th Prince of Leiningen.
Born in Hanover, Lower Saxony, Germany, Alexandra is the youngest daughter of Ernest Augustus, Prince of Hanover( 1914 – 1987), and his wife, Princess Ortrud of Schleswig- Holstein- Sonderburg- Glücksburg( 1925–1980).
Her eldest brother is Ernst August, Prince of Hanover, current head of the House of Hanover and her sister- in- law is Princess Caroline of Monaco.

Question: Where was the mother of Prince Boris Of Leiningen born?