Allie,
I don't know about services and I have not seen them mentioned on the Resorts board. You and I know that in past years they have been held at the Contemporary. I would suggest walking through the CR Lobby and Ballroom/Meeting/Convention center area today or Saturday and look for signs for Sunday morning services (in the past there have been multiple denominations holding services on Easter morning).
My theory is that these are not sponsored/offered by Disney but by local churches (who pay to rent the space) for the benefit of tourists there (as a community outreach). We've gone to Corpus Christi down in Celebration (easy drive down World Dr to get there) and they have Easter services at 730am, 9am, 1030am, 1215pm, and 530pm.
The other nearby alternative (DW's favorite) is the Basilica of the National Shrine of Mary, Queen of the Universe with services on Easter morning of 8am, 10am, 12pm and a Polish service at 230pm (I'd like to attend that service myself). The Basilica is on Vineland Ave. next to the Premium Outlet Shopping Mall. The traffic over in that direction can be more wonky later in the day.
So if you don't see any signs at the CR on Saturday (or ask) at the front desk, these are two options. Just remember to arrive early because there are always big crowds for Easter services.
Ed
PS - wish we could be there at Disney this month. We are kicking around a visit next April but AFTER Easter (which falls in early April 2026) but those plans won't come together until the 2026 FW campsite rates are released (post Easter rates are lower). Good luck to you and the family - wish we were there with you at the same time again.