My son is 2 years 2 months old. He is yet to speak. He understands everything and follows all instructions and shows us whatever he needs by pointing at the things. He speaks words like Hi, Bye, Hummm, aiiii, etc. He responds to whatever we ask by his own ways either by nodding head or smiling or in some other way. When we asked our doctor 2 months back, he told that he is lazy that is why he is not speaking. Is there any reason for concern? Do we need to observe any other things? Guidance is highly solicited. Thanking in advance.