Generally speaking in terms of size, yes. Like an infant will have a smaller brain than a two year old who will have a smaller brain size than say a 12 year old. Our brains continue to grow in size till we reach our twenties I think? It stops growing bigger in size then but it still keeps changing and developing throughout most of our life. Everything we learn in life develops the brain. So in that term it never stops growing. Its the most complex and fascinating organ of the human body!