Margaret, Marchioness of Namur
Margaret, Marchioness of Namur( c. 1194 – 17 July 1270) was ruling Marchioness of Namur in 1229- 1237.
She was the daughter of Peter II of Courtenay and Yolanda of Flanders.
Frederick III of Sicily
Frederick II (or III) (13 December 1272 – 25 June 1337) was the regent (from 1291) and subsequent King of Sicily from 1295 until his death.
He was the third son of Peter III of Aragon and served in the War of the Sicilian Vespers on behalf of his father and brothers, Alfonso ΙΙΙ and James ΙΙ.
He was confirmed as King of Trinacria (another name for the island of Sicily) by the Peace of Caltabellotta in 1302.
His reign saw important constitutional reforms: the "Constitutiones regalesCapitula alia", and "Ordinationes generales".
Peter II of Sicily
Peter II (1304 – 8 August 1342) was the King of Sicily from 1337 until his death, although he was associated with his father as co-ruler from 1321.
Peter's father Frederick III of Sicily and his mother was Eleanor, a daughter of Charles II of Naples.
His reign was marked by strife between the throne and the nobility, especially the old families of Ventimiglia, Palizzi and Chiaramonte, and by war between Sicily and Naples.
Contemporaries regarded Peter as feeble-minded.
Giovanni Villani, in his "Nuova Cronica", calls him "almost an imbecile" (Italianate Latin: "quasi un mentacatto") and Nicola Speciale, in his "Historia Sicula", calls him "pure and simplepurus et simplex").
Under Peter, the Neapolitans conquered the Lipari Islands and took the cities of Milazzo and Termini in Sicily itself.
He died after a short illness on 8 August 1342 in Calascibetta and was buried in the cathedral of Palermo.
He was succeeded by Louis, his eldest son, who was only four years old.
Kaya Alp
Kaya Alp was, according to Ottoman tradition, the son of Kızıl Buğa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertuğrul, and the great grandfather of the Ottoman Empire founder, Osman I.
Yevdokiya Lopukhina
Tsarina Eudoxia Feodorovna Lopukhina( in Moscow – in Moscow) was a Russian Tsaritsa as the first wife of Peter I of Russia, and the last ethnic Russian and non-foreign wife of a Russian monarch.
They married on 27 January 1689 and divorced in 1698.
She was the mother of Tsarevich Alexei Petrovich and the paternal grandmother of Peter II of Russia.
Beatrice of Sicily (1326–1365)
Beatrice of Sicily (5 September 1326 – 12 October 1365) was a daughter of Peter II of Sicily and his wife Elisabeth of Carinthia.
She was born into the House of Aragon.
Constance of Sicily, Queen of Aragon
Constance II of Sicily was Queen consort of Aragon as the wife of Peter III of Aragon and a pretender to the Kingdom of Sicily from 1268 to 1285.
She was the only daughter of Manfred of Sicily and his first wife, Beatrice of Savoy.
Elizabeth of Carinthia, Queen of Sicily
Elizabeth of Carinthia( 1298–1352) was an influential queen and royal family member in the Kingdom of Sicily, who lived and ruled in a tumultuous time.
The daughter of the Otto, the penultimate duke of Carinthia and lord of Carniola from the House of Gorizia, she married Peter II of Sicily in 1323 and became the Queen of Sicily.
During her time as Queen, Elizabeth ensured that the royal lineage of the Aragonese in Sicily continued.
Two sons eventually ascended the throne, Louis of Sicily and Frederick IV of Sicily.
Elizabeth was the regent for her young son Louis from 1348 until her death in 1352.
Politically, the decades leading up to Elizabeth's reign were full of conflicts between Frederick III, King of Sicily, and Robert of Naples who had the backing of the papacy in Avignon.
Famine, warfare, and plague were widespread in Europe during the mid-fourteenth century, which had a devastating impact on Sicily in particular, due to its economic expansion and prosperity in the two centuries prior.
Elizabeth's reign occurred during a period where Italian citizens were disheartened and anxious, which caused tension among the local populace.
The island was also marked by turbulent relations between the throne and Sicily's noble families, eventually degenerating into a civil war.
These internal rivalries between the noble families required the coming of age of Elizabeth's sons to resolve the fighting.
Elisabeth of Sicily, Duchess of Bavaria
Elisabeth of Sicily( 1310–1349) was a daughter of Frederick III of Sicily and Eleanor of Anjou.
Her siblings included: Peter II of Sicily and Manfred of Athens.
After her death her title was given to Georgia Lanza.
On June 27, 1328, Elisabeth married Stephen II, Duke of Bavaria, son of Louis IV, Holy Roman Emperor and Beatrix of Silesia- Glogau.
The couple had three sons and a daughter, they were:
Adelaide del Vasto
Adelaide del Vasto( Adelasia, Azalaïs)( – 16 April 1118) was countess of Sicily as the third spouse of Roger I of Sicily, and Queen consort of Jerusalem by marriage to Baldwin I of Jerusalem.
She served as regent of Sicily during the minority of her son Roger II of Sicily from 1101 until 1112.

Question: Who is the paternal grandfather of Peter Ii Of Sicily?
Answer: Peter III of Aragon