question: Who is the mother-in-law of Beatrice Of Provence?
context: [["Sanchia of Provence", ["Sanchia of Provence( c. 1225 \u2013 9 November 1261) was the third daughter of Ramon Berenguer IV, Count of Provence and Beatrice of Savoy.", "Sanchia was described as\" of incomparable beauty\"."]], ["Eldon Howard", ["Eldon Howard was a British screenwriter.", "She was the mother- in- law of Edward J. Danziger and wrote a number of the screenplays for films by his company Danziger Productions."]], ["Maria Thins", ["Maria Thins( c. 1593 \u2013 27 December 1680) was the mother- in- law of Johannes Vermeer and a member of the Gouda Thins family."]], ["Marian Shields Robinson", ["Marian Lois Robinson( n\u00e9e Shields; born July 29, 1937) is the mother of Michelle Obama, former First Lady of the United States, and Craig Robinson, a basketball executive, and the mother- in- law of former U.S. President Barack Obama."]], ["Beatrice of Provence", ["Beatrice of Provence (c. 122923 September 1267), was ruling Countess of Provence and Forcalquier from 1245 until her death, as well as Countess of Anjou and Maine, Queen of Sicily and Naples by marriage to Charles I of Naples.", "She was the fourth and youngest daughter of Ramon Berenguer IV, Count of Provence and Forcalquier by his wife Beatrice, in turn daughter of Count Thomas I of Savoy and Margaret of Geneva."]], ["Beatrice of England", ["Beatrice of England( 25 June 1242 \u2013 24 March 1275) was a member of the House of Plantagenet, the daughter of Henry III of England and Eleanor of Provence."]], ["Priscilla Pointer", ["Priscilla Marie Pointer( born May 18, 1924) is an American stage, film and television character actress.", "She began her career in the theater, including productions on Broadway.", "Later, Pointer moved to Hollywood to act in films and on television.", "She is the mother of Amy Irving, therefore making her the former mother- in- law of filmmakers Steven Spielberg and Bruno Barreto and the mother- in- law of documentary filmmaker Kenneth Bowser, Jr."]], ["Beatrice of Savoy", ["Beatrice of Savoy( c. 1198 \u2013 c. 1267) was the daughter of Thomas I of Savoy and Margaret of Geneva.", "She was Countess consort of Provence by her marriage to Ramon Berenguer IV, Count of Provence."]], ["Charles I of Anjou", ["Charles I (early 1226/12277 January 1285), commonly called Charles of Anjou, was a member of the royal Capetian dynasty and the founder of the second House of Anjou.", "He was Count of Provence (1246\u201385) and Forcalquier (1246\u201348, 1256\u201385) in the Holy Roman Empire, Count of Anjou and Maine (1246\u201385) in France; he was also King of Sicily", "(1266\u201385) and Prince of Achaea (1278\u201385).", "In 1272, he was proclaimed King of Albania; and in 1277 he purchased a claim to the Kingdom of Jerusalem.", "The youngest son of Louis VIII of France and Blanche of Castile, Charles was destined for a Church career until the early 1240s.", "He acquired Provence and Forcalquier through his marriage to their heiress, Beatrice.", "His attempts to secure comital rights brought him into conflict with his mother-in-law, Beatrice of Savoy, and the nobility.", "He received Anjou and Maine from his brother, Louis IX of France, in appanage.", "He accompanied Louis during the Seventh Crusade to Egypt.", "Shortly after he returned to Provence in 1250, Charles forced three wealthy free imperial citiesMarseilles, Arles and Avignonto acknowledge his suzerainty.", "Charles supported Margaret II, Countess of Flanders and Hainaut, against her eldest son, John, in exchange for Hainaut in 1253.", "Two years later Louis IX persuaded him to renounce the county, but compensated him by instructing Margaret to pay him 160,000 marks.", "Charles forced the rebellious Proven\u00e7al nobles and towns into submission and expanded his suzerainty over a dozen towns and lordships in the Kingdom of Arles.", "In 1263, after years of negotiations, he accepted the offer of the Holy See to seize the Kingdom of Sicily from the Hohenstaufens.", "This kingdom included, in addition to the island of Sicily, southern Italy to well north of Naples and was known as the \"Regno\".", "Pope Urban IV declared a crusade against the incumbent Manfred of Sicily and assisted Charles to raise funds for the military campaign.", "Charles was crowned king in Rome on 5 January 1266.", "He annihilated Manfred's army and occupied the \"Regno\" almost without resistance.", "His victory over Manfred's young nephew, Conradin, at the Battle of Tagliacozzo in 1268 strengthened his rule.", "In 1270 he took part in the Eighth Crusade (which had been organized by Louis IX) and forced the Hafsid caliph of Tunis to pay a yearly tribute to him.", "Charles's victories secured his undisputed leadership among the popes' Italian partisans (known as Guelphs), but his influence on papal elections and his strong military presence in Italy disturbed the popes.", "They tried to channel his ambitions towards other territories and assisted him in acquiring claims to Achaea, Jerusalem and Arles through treaties.", "In 1281 Pope Martin IV authorised Charles to launch a crusade against the Byzantine Empire.", "Charles' ships were gathering at Messina, ready to begin the campaign when a riotknown as the Sicilian Vespersbroke out on 30March 1282.", "It put an end to Charles' rule on the island of Sicily, but he was able to defend the mainland territories (or the Kingdom of Naples) with the support of France and the Holy See."]], ["Vera Mileti\u0107", ["Vera Mileti\u0107 (Serbian Cyrillic: \u0412\u0435\u0440\u0430 \u041c\u0438\u043b\u0435\u0442\u0438\u045b; 8 March 1920 \u2013 7 September 1944) was a Serbian student and soldier.", "She was notable for being the mother of Mira Markovi\u0107, posthumously making her the mother-in-law of Serbian president Slobodan Milo\u0161evi\u0107."]]]
supporting_facts: [["Beatrice of Provence", 0], ["Charles I of Anjou", 4]]
evidences: [["Beatrice of Provence", "spouse", "Charles I of Naples"], ["Charles I of Anjou", "mother", "Blanche of Castile"]]
answer: Blanche of Castile