Sounds like fun! I think long sleeve singlets are great and also skivvies for the cold. During the night with a fire it would prob be similar to any other heated indoor place in winter I would imagine. Here where it is say 2-9 degrees at night DD wears a long sleeve singlet, flanno pjs, two light woolen rugs and sheet. Sometimes if is going to be cold we set the timer on her heater. During the day I just layer clothes in the morning and remove as it gets warmer. As long as socks are on and beanies for outside combined with layers you can't go too wrong!