Alexander, Prince of Erbach-Schönberg
Alexander, Prince of Erbach- Schönberg( 12 September 1872 – 18 October 1944) was the 2nd Prince of Erbach- Schönberg, eldest son of Gustav, 1st Prince of Erbach- Schönberg.
Countess Ferdinande Henriette of Stolberg-Gedern
Countess Ferdinande Henriette of Stolberg-Gedern, born 2 October 1699 at Gedern, Oberhessen, Hesse-Darmstadt, then in the Holy Roman Empire, was a daughter of Louis Christian, Count of Stolberg-Gedern, and Duchess Christine of Mecklenburg-Güstrow.
She died at König, Starkenburg, Hesse-Darmstadt, on 31 January 1750, at age 50.
Through her daughter Karoline she is a direct female line ancestor of Queen Victoria of the United Kingdom, King Michael of Romania, the last King of that country, King Felipe VI of Spain as well as of Carl XVI Gustaf of Sweden.
George Ernest, Count of Erbach-Wildenstein
George Ernest, Count of Erbach- Wildenstein( 7 October 1629 – 25 August 1669), was a German prince member of the House of Erbach and ruler over Wildenstein, Kleinheubach und Breuberg.
He was the third child and second( but eldest surviving son) of George Albert I, Count of Erbach- Schönberg and his first wife Magdalena, a daughter of Johann VI, Count of Nassau- Dillenburg.
George Louis, Prince of Erbach-Schönberg
George Louis, Prince of Erbach- Schönberg( 1 January 190327 January 1971) was the 3rd Prince of Erbach- Schönberg, elder son of Alexander, 2nd Prince of Erbach- Schönberg.
George Albert I, Count of Erbach-Schönberg
George Albert I, Count of Erbach- Schönberg( 16 December 1597 – 25 November 1647), was a German prince member of the House of Erbach and ruler over Schönberg, Seeheim, Reichenberg, Fürstenau and since 1643 over all the Erbach family lands.
Born in Erbach, he was the fourth child and second( but eldest surviving) son of George III, Count of Erbach- Breuberg and his fourth wife Maria, a daughter of Count Albert X of Barby- Mühlingen.
George Frederick, Count of Erbach-Breuberg
George Frederick, Count of Erbach- Breuberg( 6 October 1636 – 23 April 1653), was a German prince member of the House of Erbach and ruler over Breuberg.
He was the eldest child of George Albert I, Count of Erbach- Schönberg and his third wife Elisabeth Dorothea, a daughter of George Frederick II, Count of Hohenlohe- Waldenburg in Schillingsfürst.
George Louis I, Count of Erbach-Erbach
George Louis I, Count of Erbach- Erbach( 8 May 1643 – 30 April 1693), was a German prince member of the House of Erbach and ruler over Erbach, Freienstein, Wildenstein, Michelstadt and Breuberg.
Born in Fürstenau, he was the fifth child and third( but second surviving) son of George Albert I, Count of Erbach- Schönberg and his third wife Elisabeth Dorothea, a daughter of George Frederick II, Count of Hohenlohe- Waldenburg in Schillingsfürst.
George IV, Count of Erbach-Fürstenau
George IV, Count of Erbach- Fürstenau( 12 May 1646 – 20 June 1678), was a member of the German House of Erbach who held the fiefs of Fürstenau, Michelstadt, Reichenberg, Bad König and Breuberg.
Born in Hanau, he was the eighth child and fifth( but third surviving) son of George Albert I, Count of Erbach- Schönberg and his third wife Elisabeth Dorothea, a daughter of George Frederick II, Count of Hohenlohe- Waldenburg in Schillingsfürst.
George August, Count of Erbach-Schönberg
George August was the Count of Erbach- Schönberg and lived from 1691 to 1758.
He was the youngest son of George Albert II, Count of Erbach- Fürstenau to reach adulthood.
Countess Karoline Ernestine of Erbach-Schönberg
Countess Karoline Ernestine of Erbach-Schönberg, born 20 August 1727 (20 July, according to other sources) at Gedern, Oberhessen, Hesse-Darmstadt, in the then Holy Roman Empire, was a daughter of George August, Count of Erbach-Schönberg, and Ferdinande Henriette, Countess of Stolberg-Gedern.
She died at Ebersdorf, Thuringia, on 22 April 1796, at age 68.
Through her daughter Augusta, she was the great grandmother of Queen Victoria of the United Kingdom.

Question: Who is the maternal grandfather of Countess Karoline Ernestine Of Erbach-Schönberg?
Answer: Louis Christian, Count of Stolberg-Gedern