The Feast of the Immaculate Conception has been celebrated by the Catholic Church on December 8th since as early as the 5th Century, but does not commemorate the virginal conception of the Blessed Mary. The Feast of the Annunciation marks Virgin Mary getting mystically pregnant without any sex.
A miracle, but I believed as a young boy that Mary had had an affair and came up with a miraculous alibi accepted by her parents.
Unbelievable.
Not to the believers.