Hi AyersTG
Your niece may need some time acclimatising to the altitude, by spending a few days at say 4000, 6000, 8000 feet each and watching out for mountain altitude sickness (AMS)
http://en.wikipedia.org/wiki/Altitude_sicknessGoing straight to 9000 feet can sometimes present problems especially if your neice has never been in high mountains areas.
Ingnoring the warnig signs for AMS can sometimes be fatal.