My 24 year old daughter suddenly has a bald spot about the size of a fifty cent piece.  This came on overnight, as the day before she had her hair pulled up, and it wasn't there..It is like right behind her ear, about an inch from her hairline.  Anyone ever experience this?  She is devistated...

I'd head to the doctor. Sudden hair loss could be caused by stress or it could be a sign of something else. I would have her make an appointment.

Yes, get her an appointment. It might be a fungus, mal nurtition, lots of possibilities.

I had the same thing happen to me and it totally freaked me out. I went to the doctor and they said it was likely stress. I would still go because someone later told me I could have had alopecia. But it very well may be nothing. The hair grew back in soon after.

Several years ago I lost 40 lbs. I was not taking any vitamins, however, I thought I was getting enough calories/nutrients. I wasn't. My iron was to low (not enough protein in my diet). My hair started getting thin. Went to the doctor for blood tests. Started on vitamins immediately and within 2 months my hair started coming back. It was really scary though. I have medium/thin hair and was able to blow dry/curl it into fullness until the hair grew back.