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The Immaculate Conception is a dogma of the Catholic Church maintaining that from the moment when she was conceived in the womb of her mother St. Anne the Blessed Virgin Mary was kept free of original sin and was filled with the sanctifying grace normally conferred during baptism. Her father was St. Joachim.
In 1854 that Pope Pius IX promulgated the papal bull Ineffabilis Deus (Latin for "Ineffable God"), which defined ex cathedra the dogma of the Immaculate Conception: We declare, pronounce and define that the doctrine which holds that the Blessed Virgin Mary, at the first instant of her conception, by a singular privilege and grace of the Omnipotent God, in virtue of the merits of Jesus Christ, the Saviour of mankind, was preserved immaculate from all stain of original sin, has been revealed by God, and therefore should firmly and constantly be believed by all the faithful. —Pope Pius IX, Ineffabilis Deus, December 8, 1854. Details of Novena to the Immaculate Conception available HERE