A good question which also contains some essential information.This is often referred to as a 'pot belly' This is not uncommon in young children under 3 years of age.The usual cause is a diet which contains too much carbohydate or starches. This sounds like it could be the major factor with your little niece.Other cause are worms, which she does not have and certain illnesses such as allergies especially occuring in children with eczema and food allergies. Also important illnesses like coeliac disese. In Coeliac disease there is an intolerance to gluten found in wheat and other cereals. This is unlikely to be the cause as your niece's weight is normal. Try to get her onto a better diet with protein and lots of vegetables and her tummy sweling should soon disappear.
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