Your child has been diagnosed with hypocalcemia. This means your child doesn't have enough calcium in their blood. Calcium is a mineral that helps develop bones and teeth. It also controls heart rhythm and allows muscles to contract. Causes of hypocalcemia include lack of calcium or vitamin D in your child's diet, digestive system problems, or gland problems. Other possible causes are kidney or pancreas disease, low magnesium levels, or high phosphate levels. Here's what you need to know about home care.