I don’t think they do, because those members of the cast who have any religion at all inherited it from a religious fringe group who revered a holy revelator who was born, I think, some time about a thousand years after humanity reached the stars.
They must have some kind of winter festival, because it seems to be a thing that humans do in climates that have a winter at all. The Feast of St. Maarten the Icebreaker gets mentioned in The Maker’s Mask, but I think that’s actually a festival that comes somewhere slightly later in the year and is a celebration of ‘Hell, yeah, the winter’s coming to an end and the roads are open!’ rather than ‘Here we are in the cold, we may as well huddle together and make an occasion of it’.
So I suspect that the followers of the Holy Counsellor have some kind of saint’s day or festival of lights around this time of year, and the followers of the Prophet Razalba celebrate something or other that the Prophet Razalba did a week or two later and they both get mildly irate at being given good wishes for the wrong festival. The grues, on the other hand, love this weather but… well, they’re not what you’d call a social species.
And a very Happy Winter to you all!
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