Frederick of Luxembourg
Frederick of Luxembourg (965 – 6 October 1019), Count of Moselgau, was a son of Siegfried of Luxembourg and Hedwig of Nordgau.
By a wife whose name is unknown (certain historians give her as Ermentrude, Countess of Gleiberg), he had:
John Westley
Rev. John Westley( 1636 – 78) was an English nonconformist minister.
He was the grandfather of John Wesley( founder of Methodism).
Giselbert of Luxembourg
Giselbert of Luxembourg (c. 1007 – 14 August 1059) was count of Salm and of Longwy, then count of Luxemburg from 1047 to 1059.
He was a son of Frederick of Luxembourg, count of Moselgau, and perhaps of Ermentrude of Gleiberg.
At first count of Salm and of Longwy, on his brother Henry II's death he inherited the county of Luxembourg, as well as providing the income for the abbeys of Saint-Maximin in Trier and Saint-Willibrord in Echternach.
He got into an argument with the archbishop of Trier Poppon as to the abbaye Saint-Maximin, which was arbitrated by his brother Adalbero III, bishop of Metz.
In 1050, since the population of the town of Luxembourg had risen considerably, he expanded the city by building a new fortified wall around it.
By an unknown wife, he had:
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.
Conrad I, Count of Luxembourg
Conrad I( c. 1040 – 8 August 1086), Count of Luxembourg, was the first count of Luxembourg( 1059 – 1086), succeeding his father Giselbert of Luxembourg.
He was embroiled in an argument with the archbishop of Trier as to the abbaye Saint- Maximin in Trier which he had avowed.
The archbishop excommunicated him and Conrad had to make honourable amends and set out on pilgrimage for Jerusalem to have his excommunication lifted.
He died in Italy on the return journey.
He founded many abbeys:
Giselbert I of Bergamo
Giselbert I of Bergamo( died c.927/929) was a northern Italian nobleman.
Abd al-Muttalib
Abd al- Muttalib Shaybah ibn Hashim( c. 497 – 578) was the grandfather of Islamic prophet Muhammad.
Marie of Luxembourg, Queen of France
Marie of Luxembourg( 1304 – 26 March 1324), was by birth member of the House of Luxembourg and by marriage Queen of France and Navarre.
She was the daughter of Henry VII, Holy Roman Emperor and Margaret of Brabant.
Her two siblings were John of Luxembourg and Beatrice of Luxembourg, Queen of Hungary.
Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
Beatrice of Luxembourg
Beatrice of Luxembourg( 1305 – 11 November 1319), was by birth member of the House of Luxembourg and by marriage Queen of Hungary.
She was the youngest child of Henry VII, Holy Roman Emperor and his wife, Margaret of Brabant.
Her two siblings were John of Luxembourg and Marie of Luxembourg, Queen of France.

Question: Who is the paternal grandfather of Giselbert Of Luxembourg?
Answer: Siegfried of Luxembourg