Konrad V Kantner
Konrad V Kantner( ca. 1385 – 10 September 1439) was a duke of Oleśnica, Koźle, half of Bytom and half of Ścinawa during 1412 – 1427( with his brothers as co-rulers), since 1427 sole ruler over Oleśnica.
He was the second son of Konrad III the Old, Duke of Oleśnica, by his wife Judith.
Like his one older and three younger brothers, at the baptism he received the name of Konrad, which was characteristic in this branch of the House of Piast.
His nickname of" Kantner" was derived from the town of Kanth( pl:" Kąty Wrocławskie"), who was a property of the Oleśnica dukes since 1379.
Servillano Aquino
Servillano Aquino y Aguilar
( April 20, 1874 – February 3, 1959) was a Filipino general during the Philippine Revolution against Spain( 1896 – 1898), and the Philippine- American War( 1899 – 1902).
He served as a delegate to the Malolos Congress and was the grandfather of Benigno S." Ninoy" Aquino, Jr..
He is the great- grandfather of Benigno Aquino III, the 15th President of the Philippines.
Konrad III the Old
Konrad III the Old  (– 28 December 1412) was a Duke of Oleśnica, Koźle, half of Bytom and half of Ścinawa since 1377 (until 1403 with his father as co-ruler).
He was the only son of Konrad II the Gray, Duke of Oleśnica, by his wife Agnes, daughter of Casimir I, Duke of Cieszyn.
Konrad IV the Older
Konrad IV the Older( ca. 1384 – 9 August 1447) was a Duke of Oels( Oleśnica), Koźle, half of Bytom and half of Ścinawa during 1412– 1416( with his brothers as co-rulers), since 1416 sole ruler over Kąty( Kanth), Bierutów, Prudnik and Syców and since 1417 Bishop of Wrocław and Duke of Nysa.
He was the eldest son of Konrad III the Old, Duke of Oleśnica, by his wife Judith.
The name of Konrad was also wore by his four younger brothers; they were identified by historians only through letters and regnal numbers.
Konrad VII the White
Konrad VII the White( aft. 1396 – 14 February 1452) was a Duke of Oels/ Oleśnica, Koźle, half of Bytom and half of Ścinawa during 1416 – 1427( with his brothers as co-rulers), sole Duke of Koźle and half of Bytom during 1427 – 1450, Duke of Oleśnica during 1421 – 1450( until 1439 with his brother as co-ruler) and sole Duke of half of Ścinawa during 1447 – 1450.
He was the fourth son of Konrad III the Old, Duke of Oleśnica, by his wife Judith.
Like his three older and one younger brothers, at the baptism he received the name of Konrad, which was characteristic in this branch of the House of Piast.
Konrad II the Gray
Konrad II
the Gray  (ca. 1340 – 10 June 1403)
was a Duke of Oleśnica, Koźle and half of Bytom since 1366 and Duke of half of Ścinawa since 1397 until his death.
He was the second child but only son of Duke Konrad I of Oleśnica by his second wife Euphemia, daughter of Władysław, Duke of Koźle-Bytom.
Stanisław of Masovia
Stanisław of Masovia( pl:" Stanisław mazowiecki"; 17 May 1501 – 8 August 1524), was a Polish prince member of the House of Piast in the Masovian branch.
He was a Duke of Czersk, Warsaw, Liw, Zakroczym and Nur during 1503- 1524( under regency until 1518) jointly with his brother.
He was the eldest son of Konrad III the Red and his third wife Anna, a daughter of Mikolaj Radziwiłł" the Old", Voivod of Vilnius and the first Grand Chancellor of Lithuania.
Konrad VI the Dean
Konrad VI the Dean( ca. 1391 – 3 September 1427) was a Duke of Oleśnica, Koźle, half of Bytom and half of Ścinawa since 1416( with his brothers as co-rulers).
He was the third son of Konrad III the Old, Duke of Oleśnica, by his wife Judith.
Like his two older and two younger brothers, at his baptism he received the name of Konrad, which was characteristic in this branch of the House of Piast.
Konrad VIII the Younger
Konrad VIII the Younger( after 1397 – before 5 September 1444), was a Duke of Oleśnica, Koźle, half of Bytom and half of Ścinawa during 1416 – 1427( with his brothers as co-rulers) and sole Duke of half of Ścinawa since 1427 until his death.
He was the fifth and youngest son of Konrad III the Old, Duke of Oleśnica, by his wife Judith.
Like his four older brothers, at the baptism he received the name of Konrad, which was characteristic in this branch of the House of Piast.
Janusz III of Masovia
Janusz III of Masovia( pl:" Janusz III mazowiecki"; ca. 27 September 1502 – 9/10 March 1526), was a Polish prince member of the House of Piast in the Masovian branch.
He was a Duke of Czersk, Warsaw, Liw, Zakroczym and Nur during 1503- 1524( under regency until 1518) jointly with his brother, and sole ruler during 1524- 1526 as the last male member of the Masovian Piasts.
He was the second son of Konrad III the Red and his third wife Anna, a daughter of Mikolaj Radziwiłł" the Old", Voivod of Vilnius and the first Grand Chancellor of Lithuania.

Question: Who is Konrad Iii The Old's paternal grandfather?
Answer: Konrad I of Oleśnica