Why my 6 years old son has very dry skin and brittle nails?? what vitamin or mineral is he lacking???thanx?

feed him carrots and fruit.. eat fish twice a week aswell as a lot of meat





have a glass of oange juice everyday for the daily viamin c





you might see changesWhy my 6 years old son has very dry skin and brittle nails?? what vitamin or mineral is he lacking???thanx?
vitamins a, which can be absorbed by sunlight and vitamin d ( milk) and vitamin e (used for the skin)