it can be from 3 days to 3 months depending on how much she smokes and how often, if youve never smoked before and you take a couple hits it could be out of your system in like 3 days but if you smoke all the time it bulids up and takes longer to get rid of. but if it is in you blood it is in your piss, they take the same amount of time where it can be traced further is the hair.