Constance's governess was Bella d'Amici, an Italian noblewoman. When Constance was 13, she was married to the son of King James I of Aragon, Peter. Bella d'Amici went with her and was her chief lady-in-waiting. When Manfred was killed by Charles of Anjou in the Battle of Benevento, Constance inherited the title Queen of Sicily.
King James died on 27 July 1276, with Peter succeeding him. The coronation of Peter and Constance took place on 17 November of that year, in Saragossa.
Peter and Constance had several children. From 1282-1302 their children fought the War of the Sicilian Vespers, trying to reclaim the throne of Sicily as the heirs of Constance. At that point, the "Kingdom of Sicily" extended far beyond the island, encompassing the southern part of Italy below the Papal States.
Such a large area with its resources and alliances meant that not only Aragon, but Naples, France, and the papacy were involved, all having a stake of some kind. The final result was a division of the Kingdom of Sicily into the Kingdom of Trinacria: the island of Sicily itself, governed by the Aragonese heirs of Queen Constance, and the Kingdom of Naples: the southern half of Italy.
Constance died on 9 April 1302, not quite living to see her heirs rule Sicily, the war having concluded on 31 August of that year. She lived on, however, in the great Italian epic, the Divine Comedy by Dante Alighieri. Her father, Manfred, had been excommunicated multiple times because of opposition to the papacy. Can't III of the Purgatorio shows us those who died excommunicate, including Manfred. Manfred tells Dante that he confessed all his horrible sins before he died; this repentance saved him from Hell, but he was still denied Heaven for a time. He tells Dante that there is a chance to achieve Heaven sooner if those on Earth pray for him, and he asks Dante to tell his daughter that her prayers can help.
...which is as good a segue as any to introduce our next topic, Dante Alighieri, who did not write a work called the Divine Comedy. See you tomorrow.