Prince Munetaka
Prince Munetaka (宗尊親王) (December 15, 1242 – September 2, 1274) was the sixth "shōgun" of the Kamakura shogunate of Japan who reigned from 1252 to 1266.
He was the first son of the Emperor Go-Saga and replaced the deposed Fujiwara no Yoritsugu as "shōgun" at the age of ten.
He was a puppet ruler controlled by the Hōjō clan regents.
The deposed "shōgun" became a Buddhist monk in 1272.
His priestly name was Gyōshō.
He was a writer of Waka poetry.
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.
John Westley
Rev. John Westley( 1636 – 78) was an English nonconformist minister.
He was the grandfather of John Wesley( founder of Methodism).
Abd al-Muttalib
Abd al- Muttalib Shaybah ibn Hashim( c. 497 – 578) was the grandfather of Islamic prophet Muhammad.
Guillaume Wittouck
Guillaume Wittouck( 1749- 1829) was a Belgian lawyer and High Magistrate.
He was the Grandfather of industrialist Paul Wittouck.
Prince Koreyasu
Prince Koreyasu (惟康親王) (May 26, 1264 – November 25, 1326; reigned 1266–1289) was the seventh "shōgun" of the Kamakura shogunate of Japan.
He was the nominal ruler controlled by the Hōjō clan regents.
Prince Koreyasu was the son of Prince Munetaka who was the sixth "shōgun".
At age 25, the deposed "shōgun" became a Buddhist monk.
His priestly name was Ono-no miya.
Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
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.
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.
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.

Question: Who is Prince Koreyasu's paternal grandfather?
Answer: Emperor Go-Saga