Have fun! We started our son on skis when he was 2 1/2 and it has been a great sport for him. We live in the northeast and for him being outside every weekend getting fresh air has been great. He's 14 now and snowboarding is his favorite sport.
I am not sure where you are going but if you are going to be at a high altitude, for example Colorado, be sure to take it easy the first few days. Also keep well hydrated, even before you go. The altitude can effect anyone but I would be extra vigilant with a child with CF. My son has been to Colorado several times and has always done fine, but just be cautious.
Other than altitude and staying away from hot tubs I can't think of anything else. I guess if they have a heated outdoor pool she probably shouldn't go in that either. When my son was young we didn't know any of this and took him in the hot tub and the outdoor pool numerous times. He never cultured anything different afterwards but I wouldn't do it now .
If your daughter is in ski school just make the instructor aware she has CF. That way if anything were to happen where she needed medical attention the instructor would let ski patrol know about the CF.
In terms of fires in the fireplace for my son it has not been an issue. A lot of ski areas have very dry air anyway due to the cold weather, so the fireplace may dry the air out in your condo/chalet even more which might irritate all of you. Some fireplaces are smokey ,some aren't as bad, but again just use your best judgement in terms of what is best for your child.
Enjoy your trip.
Tara
