I must have missed the "discussion". Here is the church's stance on the Immaculate Conception. Is this what you were referring to?
491. "Through the centuries the Church has become ever more aware that Mary, 'full of grace' through God,[ .] was redeemed from the moment of her CONCEPTION. That is what the dogma of the IMMACULATE CONCEPTION confesses, as Pope Pius IX proclaimed in 1854:
The most Blessed Virgin Mary was, from the first moment of her CONCEPTION, by a singular grace and privilege of almighty God and by virtue of the merits of Jesus Christ, Saviour of the human race, preserved immune from all stain of original sin.[Pius IX, Ineffabilis Deus (1854): DS 2803.]"