Question: Who is Joan, Countess Of Chiny's paternal grandfather?

Knowledge 1: Joan, Countess of Chiny
Joan (c. 1205 – 17 January 1271) was the Countess of Chiny.Joan was the daughter of Louis IV, Count of Chiny, and Matilda of Avesnes, and became ruler of the county upon her father’s death on 7 October 1226.She married Arnold IV, Count of Loon, son of Gerard III, Count of Rieneck, and Kunigunde von Zimmern,in 1228, whereupon he assumed the role of Count of Chiny.Joan and Arnold had the following children:She was succeeded as ruler of Chiny by her husband, Arnold II, Count of Chiny. [SEP] Knowledge 2: Louis IV, Count of Chiny
Louis IV the Young (1173-7 October 1226), Count of Chiny from 1189 to 1226, son of Louis III, Count of Chiny, and Sophie.Louis was the last of the first dynasty of Counts of Chiny.Having no son, he prepared his eldest daughter Jeanne as his successor.Louis marked his reign by issuing the first postage stamp in the county.He succeeded as count in 1189 when his father died on the Third Crusade, but was under the supervision of his mother and uncle Thierry, Lord of Mellier, because of his young age.He likely participated in the Albigensian Crusade, where he died in Cahors.He married Matilda of Avesnes, widow of Nicolas IV, Lord of Rumigny, and daughter of James, Lord of Avesnes and Conde, and Adele, Lady of Guise.They had three children:Isabelle was referred to as Madame de Florenville during the in 1285, hosted by Louis' grandson Louis V, successor Count of Chiny,
Upon Louis’ death, his daughter Jeanne became Countess of Chiny until her marriage to Arnold IV, when he became the first Count of Chiny of the second dynasty as Arnold II.Louis IV was also a direct paternal descendant of Charlemagne.
Knowledge 1: Joan, Countess of Chiny
Joan (c. 1205 – 17 January 1271) was the Countess of Chiny.Joan was the daughter of Louis IV, Count of Chiny, and Matilda of Avesnes, and became ruler of the county upon her father’s death on 7 October 1226.She married Arnold IV, Count of Loon, son of Gerard III, Count of Rieneck, and Kunigunde von Zimmern,in 1228, whereupon he assumed the role of Count of Chiny.Joan and Arnold had the following children:She was succeeded as ruler of Chiny by her husband, Arnold II, Count of Chiny. [SEP] Knowledge 2: Louis, Count of Verdun
Louis I (murdered September 29, 1025), Count of Chiny (987-1025) and Count of Verdun (as Louis) (1024-1025), son of Otto I, Count of Chiny, and an unknown mother.
Upon Otto’s death, Louis became the second Count of Chiny.Virtually nothing is known about his rule in Chiny.In 1024, Reginbert, the Bishop of Verdun, appointed Louis as Count of Verdun when Count Herman of Ename, son of Godfrey the Prisoner, retired to a monastery.Herman's nephew, Godfrey the Bearded, coveted the position, and Gothelo (Herman’s brother and Godfrey’s father) invaded the city and murdered Louis.Louis married Adelaide (d. after 1025), of unknown parentage.They had two children:
Louis’ son Louis II assumed the position of Count of Chiny after his father’s death, and Godfrey the Bearded was appointed Count of Verdun.
Knowledge 1: Joan, Countess of Chiny
Joan (c. 1205 – 17 January 1271) was the Countess of Chiny.Joan was the daughter of Louis IV, Count of Chiny, and Matilda of Avesnes, and became ruler of the county upon her father’s death on 7 October 1226.She married Arnold IV, Count of Loon, son of Gerard III, Count of Rieneck, and Kunigunde von Zimmern,in 1228, whereupon he assumed the role of Count of Chiny.Joan and Arnold had the following children:She was succeeded as ruler of Chiny by her husband, Arnold II, Count of Chiny. [SEP] Knowledge 2: Louis V, Count of Chiny
Louis V (1235-1299), Count of Chiny (1268-1299), the youngest son of Arnold IV, Count of Looz and Chiny, and Jeanne, Countess of Chiny.He became Count of Chiny in 1268 when his parents entrusted him with the county before their death.In 1285, he brought to Chauvency-le-Château one of the most famous jousting tournaments (a “tournament of chivalry”) of the Middle Ages, which pitted knights from the Empire, France, Lotharingia, Hainault, Flanders, and England, against each other in two days of solo-contest jousting and a final day of massed mêlée fighting.The Tournament of Chauvency  was described in verse by the French poet Jacques Bretel.A list of the participants at the tournament, which includes nearly 100 named individuals, can be found here.Before 22 July 1257, he married Jeanne de Bar (1225-1299), widow of Frederick de (d. 1255/6) and daughter of Henry II, Count of Bar, and Philippa de Dreux.Her dowry was the castle of Salm.Jeanne already had three children from her first marriage: Henry (d.1331) sire de Blâmont and seneschal of Lorraine, Joffroi (mentioned in 1253) and Thomas ("princier" of Verdun and subsequently Bishop, d.1305).Until she became Countess of Chiny in spring 1268 she was styled as 'dame de Blâmont' and used her own seal.Louis and Jeanne had no children and, after his death, Chiny reverted to his nephew Arnold V of Looz.

Answer: Louis III, Count of Chiny