Mass obligation for 4th Sun Advent and Christmas

This year the Fourth Sunday of Advent falls on December 24, which has raised the “two-for-one” question: Can attendance at a Sunday Christmas Vigil Mass fulfill the obligation for both the Fourth Sunday of Advent and Christmas? The prevailing answer of canonists is “No,” each obligation must be fulfilled with a separate Mass. This is also the desire of Archbishop Fabre. He asks that parishioners should make every effort to attend both a Fourth Sunday of Advent Mass (either Saturday evening or Sunday morning) and a Christmas Mass (either Sunday evening or Monday). 

Basilica Mass Schedule for Fourth Sunday of Advent and Christmas:

Fourth Sunday of Advent:
Sat. Dec. 23 5:30pm English Mass
Sun. Dec. 24 7am Spanish Mass
Sun. Dec. 24 9am English Mass
Sun. Dec. 24 11:30am Missa Cantata in Latin
Sun. Dec. 24 1:30pm Spanish Mass

Solemnity of Christmas:
Sun. Dec. 24 5:30pm Christmas Vigil Mass in English (prelude music at 5pm)
Mon. Dec. 25 12am Midnight Mass - Traditional Novus Ordo in Latin (prelude music at 11:30pm Dec. 24)
Mon. Dec. 25 10am Christmas Day English Mass
Mon. Dec. 25 12pm Christmas Day Spanish Mass