My son, Noah, is nearly two, and he can only say ‘dada’ and ‘bye-bye’. He can follow simple instructions and he tells us what he wants by pointing or showing us. But the other kids in my mother’s group talk a lot, and he seems really far behind. Should I be worried about him? Dr Penny Levickis sheds light on what constitutes 'late talking' and what parents can do if they are concerned their child is having language difficulties.