Can anyone tell me how they treat a child with parathryoid problems?

Surgery or calcium: Hyperparathyroidism (excess parathyroid hormone/pth) is usually caused by a small tumor of the parathyroid gland. The treatment is usually surgery. Hypoparathyroidism (low pth) is treated with calcium and vitamin d. There are at least 25 different types of hypoparathyroidism so obviously it gets pretty complicated. Hard to answer in 400 characters.

Needs peds endo: This can be truly complicated. Only a pediatric endocrinologist is trained to take care of the medical management of a pediatric patient with parathyroid problems. I'd start there.