Daughter chews on her hair snd gets belly aches can that be a symptom of undigested hair in her stomach?

Sometimes: Hair can form a mass in the stomach called a bezoar. Early on it may cause stomach aches. Eventually it may form an obstruction, at which time she will vomit as the stomach tries to push undigested food into the intestine. At this point it becomes a problem that requires a surgeon to fix. I've seen this happen a couple of times. If she absolutely can't resist eating her hair, cut it short.

A trichobezoar or : Hairball can cause pain, nausea & vomiting or gastric ulcer. Her pediatrician may order a barium swallow (x-ray) to determine if endoscopic ( via a tube passed thru her mouth) or surgical removal is needed, depending on its size. Trim her hair very short & remove all items with fibers/ stuffing. If cognitive or emotional issues exist, seek referral to a child psychologist & psychiatrist.