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.
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.
Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
Batu Khan
Batu Khan (c. 1205–1255), also known as Sain Khan  and Tsar Batu, was a Mongol ruler and founder of the Golden Horde, a division of the Mongol Empire.
Batu was a son of Jochi and grandson of Genghis Khan.
His "ulus" was the chief state of the Golden Horde, which ruled Rus', Volga Bulgaria, Cumania, and the Caucasus for around 250 years, after also destroying the armies of Poland and Hungary.
"Batu" or "Bat" literally means "firm" in the Mongolian language.
After the deaths of Genghis Khan's sons, he became the most respected prince, called "aghaelder brother"), in the Mongol Empire.
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.
Boraqchin (Tatar)
Boraqchin Khatun was an Alchi Tatar woman.
She was the chief or senior wife of Batu Khan, and probably the mother of Sartaq Khan.
In 1257, she served as regent of the Golden Horde on behalf of Ulaghchi, who was Sartaq's son and probably her grandson.
After Ulaghchi's death, Berke ousted Boraqchin and took control of the Golden Horde.
Sartaq Khan
Sartaq (or Sartak, Sartach) Khan (died 1257) was the son of Batu Khan and Regent Dowager Khatun Boraqchin of Alchi Tatar.
Sartaq succeeded Batu as khan of the Golden Horde.
In 1252, Alexander Nevsky met with Sartaq at Sarai.
Alexander received "yarlyk" (license) to become Grand Duke of Vladimir in vassalage to the Kipchak Khanate.
According to Lev Gumilev he became Sartaq's "anda" (sworn brother, probably akin to blood brother) and an adopted son of Batu Khan.
His reign as khan of the Golden Horde was short-lived.
He died in 1256 before returning from Great Khan Möngke's court in Mongolia, less than one year after his father, probably having been poisoned by his uncles Berke and Berkhchir.
Sartaq was succeeded by Ulaqchi briefly in 1257, before his uncle Berke succeeded to the throne.
It is not clear whether Ulaqchi was his brother or his son.
Sartaq's daughter Feodora (or Theothiure) was the wife of Gleb Vasilkovich, first Prince Belozersky of Beloozero and Rostov, a grandson of Konstantin of Rostov.
Guillaume Wittouck
Guillaume Wittouck( 1749- 1829) was a Belgian lawyer and High Magistrate.
He was the Grandfather of industrialist Paul Wittouck.
John Westley
Rev. John Westley( 1636 – 78) was an English nonconformist minister.
He was the grandfather of John Wesley( founder of Methodism).

Question: Who is the paternal grandfather of Sartaq Khan?
Answer: Jochi