Hello XXXXXX
I can understand your concern regarding this.

You have mentioned the history of VSD closure and medication. It seems that his developmental history is normal and there is no significant maternal illness or medication during pregnancy. So I assume these are not the causes of delayed speech in your case.

There may be various causes for delayed speech. Following are the probable causes which I consider in your case.

Delayed speech may be due to 'Developmental language delay' a condition, which is more common in boys and usually history of delayed speech in family members are present. In this condition development, intelligence and comprehension is absolutely normal. Here no intervention is needed and prognosis is excellent. Child develop normal speech by the age of school entry.

Expressive language disorder or developmental expressive aphasia is another condition in which prognosis is not that good. Child use gestures to supplement their verbal limit. These child may develop Dyslexia in later childhood if not intervened.

Before labeling the child as a case of developmental delay or maturation delay a proper hearing assessment is must to rule out hearing problem as this is a major cause of pathological delayed speech.

It is not clear whether your child is not able to speak anything or can speak mono or bisyllable.

So I would suggest you to consult a pediatrician for proper history and clinical examination and also to investigate for hearing problem like BERA, OAE.

I will be glad to answer if you have any further query.
Wish you and your family good health
With regards

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