Hi, my son is aged 2.8years. when he was 1.5 years he could speak some words, some time last year January the house help was changed. after the new one came the boy couldn't speak the words he used to speak and again you could find him seating some where looking as if he is stressed. When i arrive home from work he could come running to the door but this days he is not concerned at all. When i speak to him the words he used to he can't speak them again, You call him and he doesn't respond. I'm a worried Father, What do i do, i want him to remember what he used to do, to say. Where did we go wrong in bringing the boy up. He is turning three May 29th, he can only speak just one world "hello" he repeats that all the time. Is there a medication i can give him to change the situation? Please advice