Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
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.
Henry Bryant (naturalist)
Henry Bryant( May 12, 1820 – February 2, 1867) was an American physician and naturalist.
He was the grandfather of Henry Bryant Bigelow.
John I Doukas of Thessaly
John I Doukas , Latinized as Ducas, was an illegitimate son of Michael II Komnenos Doukas, Despot of Epirus in –1268.
After his father's death, he became ruler of Thessaly from to his own death in 1289.
From his father's family he is also inaccurately known as John Angelos.
Married to a Thessalian Vlach woman, John first appears leading Vlach troops alongside his father in the lead-up to the Battle of Pelagonia in 1259.
His defection to the camp of Emperor Michael VIII Palaiologos was crucial in the battle, which ended with the crushing defeat of the Epirotes' Latin allies and opened the way for the recovery of Constantinople and the re-establishment of the Byzantine Empire under Palaiologos in 1261.
John quickly returned to the side of his father and brother, Nikephoros, and assisted them in recovering Epirus and Thessaly.
After Michael II died, John Doukas became ruler of Thessaly with his seat at Neopatras, whence Western chroniclers often erroneously called him "Duke of Neopatras".
Although Michael VIII Palaiologos engaged him in a marriage alliance and awarded him with the high title of "sebastokratōr", John remained the foremost of Palaiologos' Greek opponents throughout the latter's reign.
A staunch opponent of the Union of the Churches promoted by Palaiologos for political reasons, he provided refuge to several political opponents of the emperor, and even convoked synods that anathematized Palaiologos and the supporters of the Union.
He resisted several attempts by Byzantine armies to conquer Thessaly, and allied himself with Palaiologos' Latin enemies, including the Duchy of Athens and Charles of Anjou.
He died in 1289, leaving the rule of Thessaly to his sons, Constantine and Theodore.
John Westley
Rev. John Westley( 1636 – 78) was an English nonconformist minister.
He was the grandfather of John Wesley( founder of Methodism).
Fujiwara no Nagara
, also known as Fujiwara no Nagayoshi, was a Japanese statesman, courtier and politician of the early Heian period.
He was the grandfather of Emperor Yōzei.
Prithvipati Shah
Prithvipati Shah( ?–1716) was the king of the Gorkha Kingdom in the Indian subcontinent, present- day Nepal.
He was the grandfather of Nara Bhupal Shah.
Abd al-Muttalib
Abd al- Muttalib Shaybah ibn Hashim( c. 497 – 578) was the grandfather of Islamic prophet Muhammad.
Helena Doukaina Angelina
Helena Doukaina Angelina ("Helene Doukaina Angelina") was a Greek noblewoman of Thessaly and Queen-consort of medieval Serbia.
Her parents were John I Doukas of Thessaly and his wife Hypomone (a daughter of the Thessalian Vlach chieftain Taronas).
In ca.
1273/76, Helena married Serbian king Stefan Milutin (r. 1282–1321), but Milutin abandoned her in ca.
1283.
It is possible that their sons were Kings Stefan Konstantin and Stefan Dečanski.
It seems Helena then returned to Greece.
Guillaume Wittouck
Guillaume Wittouck( 1749- 1829) was a Belgian lawyer and High Magistrate.
He was the Grandfather of industrialist Paul Wittouck.

Question: Who is Helena Doukaina Angelina's paternal grandfather?
Answer: Michael II Komnenos Doukas