Christmas eve on Sunday

In Paul Turner's Blog by Paul Turner

Q:  This year Christmas Eve falls on Sunday.  Our parish normally has a Sunday evening Mass.  We are trying to configure our mass schedule as best as we can to respect the 4th Sunday of Advent and Christmas Eve / Day masses.  We are also a bilingual parish so we need to provide for sufficient liturgies in English and in Spanish.  If a person were to participate in a Christmas Eve liturgy – would that fulfill both obligations for Sunday and Christmas?
A:  That is a canonical question, not a liturgical one. There are canon lawyers who believe that it does count because of the way that canon law reckons time. But there are others who disagree.

God knows the answer. To be on the safe side, I advise people to make time for both celebrations.