Ds is 6 months old and has been coughing on and off since birth - a sharp barking cough. He eats well and is a very happy baby but is not gaining weight as he should (he is now below the 9th percentile). Docs say his chest is clear and health visitor is advising to start giving him more iron rich foods such as lentils and chicken. Anyone else experienced poor weight gain and cough like this (may not be connected). I am very worried about him