After looking at the two links supplied above by ClaireBear and Micca, I take back what I may have implied about newly-written solsice songs. There are a couple of very nice lyrics there, and the tunes are undoubtedly worth learning.

No one here knows your audience as well as you do, and you have to decide what approach to take.

If you think they would be happiest with something familiar that they can sing along with, you have a number of choices. It may be necessary to point out to the group that a song like, say "Deck the Halls," does *not* make any explicit mention of Christmas but refers only to "Yuletide." Without an introduction that includes a bit of such "edu-tainment," listeners would likely think of it as just another Christmas carol.

On the other hand, they might be ready and willing to listen to something entirely new and different. Your call.

At least you only need "a song or two," not a whole evening's program of songs that fit the requirements!