In Argentina, Mother's Day is celebrated on the third Sunday of October. The holiday was originally celebrated on 11 October, the old liturgical date for the celebration of the Maternity of the Blessed Virgin Mary but after the Second Vatican Council, which moved the Virgin Mary festivity to 1 January, the Mother's Day started to be celebrated the third Sunday of October because of popular tradition. Argentina is the only country in the world that celebrates Mother's Day on this date.