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.
Shubhendra Shankar
Shubhendra Shankar (30 March 1942 – 15 September 1992), also known as Shubho Shankar, was a graphic artist, musician and composer.
He was the son and the eldest child of musicians Ravi Shankar and Annapurna Devi.
Abd al-Muttalib
Abd al- Muttalib Shaybah ibn Hashim( c. 497 – 578) was the grandfather of Islamic prophet Muhammad.
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 Westley
Rev. John Westley( 1636 – 78) was an English nonconformist minister.
He was the grandfather of John Wesley( founder of Methodism).
Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
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.
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.
Guillaume Wittouck
Guillaume Wittouck( 1749- 1829) was a Belgian lawyer and High Magistrate.
He was the Grandfather of industrialist Paul Wittouck.
Annapurna Devi
Annapurna Devi (1927–13 October 2018) was an Indian surbahar (bass sitar)
player of Hindustani classical music.
She was given the name 'Annapurna' by former Maharaja Brijnath Singh of the former Maihar Estate (M.P.), and it was by this name that she was popularly known.
She was the daughter and disciple of Allauddin Khan, the founder of Maihar gharana, and the first wife of the sitar player, Ravi Shankar.
After her separation from Ravi Shankar, she moved to Bombay and never performed again in public.
She remained a private person, yet continued to teach music for free.
Her students include many notable disciples including Hariprasad Chaurasia, Nityanand Haldipur and Nikhil Banerjee.

Question: Who is the maternal grandfather of Shubhendra Shankar?
Answer: Allauddin Khan