I agree with both above. Period. Stress. Lack of sleep. Good triggers me. Peppers.

Both I have found that if i dont get at least 9 hours in bed it triggers pain. I also take a bath with epson salt that I have found to cut down stiffness in the morning.

Stress, lack of sleep, changes in weather (when the barometric pressure drops , when it gets super cold, rain and storms),

The best way to figure out what causes her flares is to keep a daily journal. Track her activity levels and her diet. It may take some time to notice any patterns but is the most accurate.

If your daughter has periods...she probably flares during or just before her period. I have found that sugary products make me hurt more too. I also think there are certain chemicals that bother me. I use a hand sanitizer at work that with frequent use I can actually taste. Hope that helps!