Question: Who is Walter Stewart, Earl Of Atholl's paternal grandmother?

Knowledge 1: Walter Stewart, Earl of Atholl
Walter Stewart, Earl of Atholl, Strathearn and Caithness (c. 1360 – 26 March 1437) was a Scottish nobleman, the son of Robert II of Scotland.Stewart was an enthusiastic advocate of the ransom and return to Scotland of the future king in exile, James I, in 1424.In 1425 he served as a member of the jury of 21 which tried and executed his nephew Murdoch Stewart, 2nd Duke of Albany.Eventually, however, Atholl turned against the King and conspired in his assassination in 1437.He was tried for murder and was executed after 3 days of gruesome torture. [SEP] Knowledge 2: Robert II of Scotland
Robert II (2 March 1316 – 19 April 1390) reigned as King of Scots from 1371 to his death as the first monarch of the House of Stewart.He was the son of Walter Stewart, 6th High Steward of Scotland and of Marjorie Bruce, daughter of the Scottish king Robert the Bruce by his first wife Isabella of Mar.Edward Bruce, younger brother of Robert the Bruce, was named heir presumptive but died without heirs on 3 December 1318.Marjorie had died probably in 1317 in a riding accident and parliament decreed her infant son, Robert Stewart, as heir presumptive, but this lapsed on 5 March 1324 on the birth of a son, David, to King Robert and his second wife, Elizabeth de Burgh.Robert Stewart became High Steward of Scotland on his father's death on 9 April 1326, and in the same year parliament confirmed the young Steward as heir should Prince David die without a successor.In 1329 King Robert I died and the six-year-old David succeeded to the throne under the guardianship of Thomas Randolph, Earl of Moray.Edward Balliol, son of King John Balliol—assisted by the English and those Scottish nobles who had been disinherited by Robert I—invaded Scotland inflicting heavy defeats on the Bruce party on 11 August 1332 at Dupplin Moor and Halidon Hill on 19 July 1333.Robert, who had fought at Halidon joined his uncle, King David in refuge in Dumbarton Castle.David escaped to France in 1334 and parliament, still functioning, appointed Robert and John Randolph, 3rd Earl of Moray as joint Guardians of the kingdom.Randolph was captured by the English in July 1335 and in the same year Robert submitted to Balliol bringing about the removal of his guardianship.The office was reinstated in 1338 and Robert held it until David's return from France in June 1341.Hostilities continued and Robert was with David at the Neville's Cross on 17 October 1346 and either escaped or fled the fieldbut David was captured and remained a prisoner until he was ransomed in October 1357.Robert married Elizabeth Mure around 1348, legitimising his four sons and five daughters.His subsequent marriage to Euphemia de Ross in 1355 produced two sons and two surviving daughters.Robert rebelled against the King in 1363 but submitted to him following a threat to his right of succession.David died in 1371 and Robert succeeded him at the age of fifty-five.The border magnates continued to attack English-held zones in southern Scotland and by 1384, the Scots had re-taken most of the occupied lands.Robert ensured that Scotland was included in the Anglo-French truce of 1384 and that was a factor in the coup in November when he lost control of the country first to his eldest son, John, and then from 1388 to John's younger brother, Robert.King Robert died in Dundonald Castle in 1390 and was buried at Scone Abbey.
Knowledge 1: Robert II of Scotland
Robert II (2 March 1316 – 19 April 1390) reigned as King of Scots from 1371 to his death as the first monarch of the House of Stewart.He was the son of Walter Stewart, 6th High Steward of Scotland and of Marjorie Bruce, daughter of the Scottish king Robert the Bruce by his first wife Isabella of Mar.Edward Bruce, younger brother of Robert the Bruce, was named heir presumptive but died without heirs on 3 December 1318.Marjorie had died probably in 1317 in a riding accident and parliament decreed her infant son, Robert Stewart, as heir presumptive, but this lapsed on 5 March 1324 on the birth of a son, David, to King Robert and his second wife, Elizabeth de Burgh.Robert Stewart became High Steward of Scotland on his father's death on 9 April 1326, and in the same year parliament confirmed the young Steward as heir should Prince David die without a successor.In 1329 King Robert I died and the six-year-old David succeeded to the throne under the guardianship of Thomas Randolph, Earl of Moray.Edward Balliol, son of King John Balliol—assisted by the English and those Scottish nobles who had been disinherited by Robert I—invaded Scotland inflicting heavy defeats on the Bruce party on 11 August 1332 at Dupplin Moor and Halidon Hill on 19 July 1333.Robert, who had fought at Halidon joined his uncle, King David in refuge in Dumbarton Castle.David escaped to France in 1334 and parliament, still functioning, appointed Robert and John Randolph, 3rd Earl of Moray as joint Guardians of the kingdom.Randolph was captured by the English in July 1335 and in the same year Robert submitted to Balliol bringing about the removal of his guardianship.The office was reinstated in 1338 and Robert held it until David's return from France in June 1341.Hostilities continued and Robert was with David at the Neville's Cross on 17 October 1346 and either escaped or fled the fieldbut David was captured and remained a prisoner until he was ransomed in October 1357.Robert married Elizabeth Mure around 1348, legitimising his four sons and five daughters.His subsequent marriage to Euphemia de Ross in 1355 produced two sons and two surviving daughters.Robert rebelled against the King in 1363 but submitted to him following a threat to his right of succession.David died in 1371 and Robert succeeded him at the age of fifty-five.The border magnates continued to attack English-held zones in southern Scotland and by 1384, the Scots had re-taken most of the occupied lands.Robert ensured that Scotland was included in the Anglo-French truce of 1384 and that was a factor in the coup in November when he lost control of the country first to his eldest son, John, and then from 1388 to John's younger brother, Robert.King Robert died in Dundonald Castle in 1390 and was buried at Scone Abbey. [SEP] Knowledge 2: John Stewart, 2nd Earl of Atholl
John Stewart, 2nd Earl of Atholl was the second Earl of Atholl.He fought in the Battle of Flodden on 9 September 1513.
Knowledge 1: Walter Stewart, Earl of Atholl
Walter Stewart, Earl of Atholl, Strathearn and Caithness (c. 1360 – 26 March 1437) was a Scottish nobleman, the son of Robert II of Scotland.Stewart was an enthusiastic advocate of the ransom and return to Scotland of the future king in exile, James I, in 1424.In 1425 he served as a member of the jury of 21 which tried and executed his nephew Murdoch Stewart, 2nd Duke of Albany.Eventually, however, Atholl turned against the King and conspired in his assassination in 1437.He was tried for murder and was executed after 3 days of gruesome torture. [SEP] Knowledge 2: John Stewart, 2nd Earl of Atholl
John Stewart, 2nd Earl of Atholl was the second Earl of Atholl.He fought in the Battle of Flodden on 9 September 1513.

Answer: Marjorie Bruce