My son is 4 years old yet cannot talk. only babbles some single letters like mamma babba dadda nanna etc. His allround growth is also less than 4 years and he resembles a small child of only 2-2.5 years. We consulted Paediatric neurologist of Apollo Chennai and she said after MRI that its a case of delayed brain development due to something called Multiple Covernuma and prescribed two medicines but though my son s response has shown much betterment since then but his speech has not been started yet after a year of taking medicines. What should we do?