Four years old is in the critical period of growth and development of children, and the yellowing of the face is mainly due to malnutrition.
First of all, you should go to the hospital for blood routine and other related examinations to clarify whether there is anemia and other diseases. At the same time, you should adjust the diet structure, reasonably supplement nutrients, develop a balanced and healthy diet, and reasonably supplement the nutrients that children lack according to the doctor’s instructions.