Question
My son turned four in November, and he can only call out ‘Dad’ and ‘Mom’. He understands everything and knows everything, but he can’t express them.
Answer
Based on the current situation you described, most of the time this kind of phenomenon in children is due to a lack of certain elements leading to abnormal growth and development. In that case, we can give the child vitamin oral liquid, calcium gluconate plus zinc oral solution for a period of time, or some calcium iron zinc oral solution and vitamin A, D capsules.