Frederick XI, Count of Hohenzollern
Friedrich XI, Count of Hohenzollern( died 26 November 1401), nicknamed" Friedrich the Elder" was a German nobleman.
He was a member of the House of Hohenzollern and a ruling Count of Hohenzollern- Hechingen.
Duchess Maria Isabella of Württemberg
Duchess "Maria Isabella" Philippine Theresia Mathilde Josephine of Württemberg  (30 August 1871 – 24 May 1904) was a member of the House of Württemberg and a Duchess of Württemberg by birth and a member of the House of Wettin and a Princess of Saxony through her marriage to Prince Johann Georg of Saxony.
Prince Johann Georg of Hohenzollern
Johann Georg, Prince von Hohenzollern ("Johann Georg
Carl Leopold Eitel-Friedrich Meinrad Maria Hubertus Michael"; 31 July 1932 – 2 March 2016) was a German prince, and through his marriage to Princess Birgitta of Sweden, was brother-in-law of King Carl XVI Gustaf of Sweden.
Prince Johann Georg was the sixth child of Frederick, Prince of Hohenzollern
(Heiligendamm 30 August 1891 – Krauchenwies 6 February 1965) and his wife Princess Margarete Karola of Saxony
(Dresden 24 January 1900 – Freiburg im Breisgau 16 October 1962).
Johann Georg, Prince of Hohenzollern-Hechingen
Johann Georg of Hohenzollern- Hechingen( born 1577 in Hechingen; died 28 September 1623 in Hechingen) was the first Prince of Hohenzollern- Hechingen.
Hubba bint Hulail
Hubba bint Hulail was the grandmother of Hashim ibn' Abd Manaf, thus the great- great- great- grandmother of the Islamic" Nabī"( Prophet) Muhammad ibn Abdullah.
Prince Hubertus of Hohenzollern
Prince Hubertus of Hohenzollern( Hubertus Gustav Adolf Veit Georg Meinrad Maria Alexander)( born 10 June 1966) is the third child of Prince Johann Georg of Hohenzollern and of his wife Princess Birgitta of Sweden, sister of King Carl XVI Gustaf of Sweden.
Hubertus was born in Munich, Germany.
Prince Carl Christian of Hohenzollern
Prince Carl Christian of Hohenzollern( born 5 April 1962) is the eldest child of Prince Johann Georg of Hohenzollern and of his wife Princess Birgitta of Sweden, sister of King Carl XVI Gustaf of Sweden.
Frederick XII, Count of Hohenzollern
Friedrich XII, Count of Hohenzollern, nickname Friedrich the Oettinger( before 1401 – 1443) was a German nobleman.
He was a member of the Swabian branch of the House of Hohenzollern.
His father was Friedrich XI, Count of Hohenzollern; his younger brother and rival was Eitel Friedrich I, Count of Hohenzollern.
Johann, Prince of Hohenzollern-Sigmaringen
Prince Johann of Hohenzollern- Sigmaringen( 17 August 1578 in Sigmaringen – 22 March 1638 in Munich), was the ruling Count of Hohenzollern- Sigmaringen from 1606 to 1623.
He was elevated to the rank of prince in 1623 and so was" Prince" of Hohenzollern- Sigmaringen from 1623 until his death.
Frederick, Prince of Hohenzollern
Frederick, Prince of Hohenzollern  (30 August 1891 in Heiligendamm, Mecklenburg-Schwerin – 6 February 1965 in Krauchenwies, Baden-Württemberg, Germany) was the eldest son of William, Prince of Hohenzollern and Princess Maria Teresa of Bourbon-Two Sicilies.
He had a twin brother, Franz Joseph, Prince of Hohenzollern-Emden, who was born a few minutes after he was.

Question: Who is the paternal grandmother of Prince Johann Georg Of Hohenzollern?
Answer: Princess Maria Teresa of Bourbon-Two Sicilies