Safety for Kids questions

Hi all, new guy here!

Are there any good rules for safety for a 9 year old girl spending time up in the mountains?
She is a good skier, and used to being in the snow, but only in controlled areas. She won't be outside by herself often, but it would be nice if she could play near the house.

Are there any good rules that we should pass along to her for when she is outside?

Anything to avoid? Snow falling dangers?

Thanks in advance
-Geoff