Why is my pediatrician referring me to a 'state' nutritionist?

Ask the pediatrician why he referred you to the state nutritionist. Is your son healthy and still playing well? My daughter was extremely petite (below the scales and didn't weight 20 pounds until she was 18 months but that was due to genetics). She was, however, gaining weight at each visit, she was just small. If you don't like the pediatrician's answers to your questions, then go get a second opinion.