Maren and Chris are lighting the tree...
Carrie Underwood adds Vegas dates...

Maren Morris and Chris Stapleton will perform for the National Christmas Tree Lighting Ceremony in Washington D.C. on Sunday. 
The show, hosted by LL Cool J, airs on CBS.

Following a sold-out debut show at Resorts World Theatre in Las Vegas, Carrie Underwood announced six more performances in the Reflection: The Las Vegas Residency.
The new shows are all in May, and tickets go on sale December 6th.