4th Sunday of Advent/Christmas Eve
In this case, there are two distinct obligations to attend Mass:
the Sunday obligation and the Christmas obligation.
Sunday obligation options at St. Monica:
12/23 - 5PM Mass
12/24 - 7:30AM, 9AM, 11AM, or 1PM (Spanish) Masses
Christmas obligation options at St. Monica:
12/24 - 4PM, 6PM, 8PM (Spanish), or 11PM Masses
12/25 - 9AM or 11AM Masses