Not expert, that Merrenburg one with brother of Countess of Torby and his sons
The founder of the counts of Merenberg line is Prince Nikolaus Wilhelm of Nassau, which is from the Nassau-Weilburg line.
https://en.wikipedia.org/...ikolaus_Wilhelm_of_NassauNikolaus Wilhelm, Prince of Nassau (1832 - 1905), was the only son of Wilhelm, Duke of Nassau by his second wife Princess Pauline of W?rttemberg. Therefore Nikolaus was the younger half brother of Adolphe, Duke of Nassau who became Grandduke of Luxemburg.
Nikolaus Wilhelm had married morganatically in London on 1 July 1868 Natalya Alexandrovna Pushkina. She was divorced from the Russian General Mikhail Leontievich von Dubelt, by whom she had a daughter. In 1868, George Victor, Prince of Waldeck and Pyrmont created her Countess von Merenberg. They had three children:
1. Countess Sophie von Merenberg (1 June 1868 - 14 September 1927); created
Countess de Torby in 1891; married in Sanremo on 26 February 1891, Grand Duke Michael Mikhailovich of Russia (16 October 1861 - 26 April 1929). They had issue.
2. Countess Alexandrine von Merenberg (14 December 1869 - 29 September 1950); married in London in 1914 Argentine Don Maximo de Elia (1851 - 1929), no issue.
3. Count Georg Nikolaus von Merenberg (13 February 1871 - 31 May 1948); married firstly on 12 May 1895 in Nice, Princess Olga Alexandrovna Yurievskaya (8 November 1873 - 10 August 1925), daughter of Alexander II of Russia and his morganatic second wife, Princess Ekaterina Mikhailovna Dolgorukova, and had issue; married, secondly, on 2 January 1930 in Wiesbaden, Adelheid Moran-Brambeer ( 18 October 1875 - 12 May 1942), no issue.
Nikolaus-Wilhelm was in line of succession (Nassau and related). This also seem to include is male offspring. Other brothers of Nikolaus-Wilhelm and Adolphe had died young or unmarried (and childless). Adolphe's son Guilleaume IV had only daughters, and based on the Nassau family pact the succession in Luxembourg would go to Nikolaus and his male offspring. At the death of his uncle, Prince Nikolaus-Wilhelm in 1905, the only other legitimate male in the House of Nassau-Weilburg was Guilleaume's cousin, Georg Nikolaus, Count of Merenberg, the product of a morganatic marriage. So in 1907, Guilleaume declared the Counts of Merenberg non-dynastic, naming his own eldest daughter Marie-Ad?la?de (1894?1924) as heir presumptive to the grand ducal throne.
