question: Who is the paternal grandfather of Gilbert De Umfraville, Earl Of Angus?
context: [["Gilbert de Umfraville, Earl of Angus", ["Gilbert de Umfraville, Earl of Angus", "(r. 1246\u20131308) was the first of the Anglo-French de Umfraville line to rule the Earldom of Angus in his own right.", "His father was Gilbert de Umfraville (d. shortly before 13 March 1245), a Norman, and feudal Baron of Prudhoe in Northumberland, and his mother was Matilda, Countess of Angus.", "He succeeded his father in infancy.", "He also carried on the line of the earlier Gaelic earls through his mother.", "He succeeded her sometime after 1247 (when she was still living with her third husband Richard de Dover) as an infant, certainly no older than three.\nSimon de Montfort, 6th Earl of Leicester, paid \u00a310,000 to act as Gilbert's warden.", "Gilbert eventually grew into his inheritance, and although he was primarily an English magnate, there are still a few of his recorded grants.", "Gilbert was the nominal ruler of the province for more than half a century.", "As Earl of Angus", "he was summoned in 1276 for a campaign in Gwynedd against Llywelyn ap Gruffudd.", "In 1284 he attended the parliament with other Scottish noblemen who acknowledged Margaret of Norway as the heir to King Alexander.", "In 1296 he again joined Edward I in his conquest of Scotland.", "He also founded a chantry for two priests at Prudhoe castle to celebrate mass daily.", "He died in 1308, and was succeeded by his second son, Robert de Umfraville, Earl of Angus.", "Gilbert was buried in Hexham Abbey his effigy survives and can be seen."]], ["William Douglas, 2nd Earl of Angus", ["William Douglas, 2nd Earl of Angus (24 February 1398 \u2013 October 1437) was a Scottish nobleman and soldier.", "The son of George Douglas, 1st Earl of Angus and Princess Mary of Scotland, he was a grandson of King Robert III.", "The story of Angus' life is interwoven with that of his uncle and King, James I of Scotland.", "Angus was born about 1398 at Tantallon Castle in East Lothian.", "He inherited the Earldom of Angus in 1402, following his father's death of the plague whilst in English captivity, following the Battle of Homildon Hill."]], ["Gilbert de Umfraville", ["Gilbert de Umfraville (died 1245) was a 13th-century baron.", "Gilbert was the eldest son of Richard de Umfraville, Lord of Redesdale.", "He succeeded his father as Lord of Redesdale and Baron Prudhoe from 1226 at his seat of Prudhoe Castle.", "He also had lands at Otterburn."]], ["George Douglas, 4th Earl of Angus", ["George Douglas, 4th Earl of Angus, Lord Douglas, Abernethy and Jedburgh Forest( c. 1427 \u2013 12 March 1463) was a Scottish nobleman.", "He was the son of William Douglas, 2nd Earl of Angus and Margaret Hay of Yester.", "Known as the Great Earl of Angus, he succeeded to the Earldom following the death of his childless brother James Douglas, 3rd Earl of Angus in 1446.", "He was to become the first Red Chief of Douglas."]], ["Gille Cr\u00edst, Earl of Angus", ["Gille Cr\u00edst, Earl of Angus ruled until 1206 as Mormaer of Angus.", "He was a son of Gille Brigte of Angus and younger brother of Adam of Angus.", "Almost nothing is known of him except that he married Marjorie of Huntingdon, the daughter of Henry of Scotland and Ada de Warenne, and that he was succeeded by his son Donnchad before 1206.", "His daughter Beth\u00f3c( Beatrix) was married to Walter Stewart, 3rd High Steward of Scotland and was mother to Alexander Stewart, 4th High Steward of Scotland.", "Marjorie of Huntingdon married secondly( as his second wife), Sir William de Lindsay of Ercildum and Crawford( born c. 1148 \u2013 died c. 1200).", "Gille Cr\u00edst, Earl of Angus and Marjorie of Huntingdon were ancestors of Robert I( known as Robert the Bruce), King of Scots( b. 11 July 1274- d. 7 June 1329).", "Gille Cr\u00edst, 4th Earl of Angus had by his first wife, Marjorie of Huntingdon( youngest daughter of Henry of Scotland, Earl of Huntingdon and his wife, Ada de Warenne), the following son and daughter:", "Gille Cr\u00edst, 4th Earl of Angus had by his second wife, Ingibiorg Ericsdottir of Caithness( daughter of Eric Thorliotsson), the following son:"]], ["Robert de Umfraville, Earl of Angus", ["Robert de Umfraville, 8th Earl of Angus, of Prudhoe, Chollerton, Harbottle, and Whelpington, Northumberland( 1277 \u2013 1325) was an Anglo- Norman baron in Northumberland and the eighth Earl of Angus."]], ["Archibald Douglas, 6th Earl of Angus", ["Archibald Douglas, 6th Earl of Angus( c. 148922 January 1557) was a Scottish nobleman active during the reigns of James V and Mary, Queen of Scots.", "He was the son of George, Master of Angus, who was killed at the Battle of Flodden, and succeeded as Earl of Angus on the death of his grandfather, Archibald."]], ["Gilbert of St Leonard", ["Gilbert de St Leonard( or Gilbert de St. Leofard; died 1305) was a medieval Bishop of Chichester."]], ["John Comyn (died 1242)", ["John Comyn, Earl of Angus jure uxoris, was a son of William Comyn, Lord of Badenoch later the Earl of Buchan and became the Earl of Angus, jure uxoris of his wife Matilda, heiress of M\u00e1el Coluim, Earl of Angus.", "He died in 1242."]], ["Margaret Stewart, Countess of Angus", ["Margaret Stewart, Countess of Angus and Mar( died 1417) was Countess of Angus and Lady of Abernethy in her own right.", "Her father was Thomas Stewart, 2nd Earl of Angus.", "She was the widow of Thomas, Earl of Mar.", "By an illicit affair with William Douglas, 1st Earl of Douglas, husband of the Earl of Mar's sister, she became the mother of George Douglas, 1st Earl of Angus( c. 1380- 1403), and secured a charter of her estates for her son, to whom in 1389 the title was granted by King Robert II."]]]
supporting_facts: [["Gilbert de Umfraville, Earl of Angus", 2], ["Gilbert de Umfraville", 1]]
evidences: [["Gilbert de Umfraville, Earl of Angus", "father", "Gilbert de Umfraville"], ["Gilbert de Umfraville", "father", "Richard de Umfraville"]]
answer: Richard de Umfraville