D.S.
I would get it checked out by the doctor. Does she have any circular bald spots where the hair is falling out? That could be a condition called Alopecia and a doctor needs to be seen to help it out. Is her scalp showing at all in the areas of the hair loss. Normal hair loss daily is up to 100 hairs daily I believe (it's along time since I went to beauty school) so anything over that can be something else and should be seen by a doctor. Also, try not to pull it back in a tight ponytail that will also make things worse. Certain times of the year hair falls out more then other times, however that is usually the fall. Just to put your mind at ease get it checked out.