Thank you for posting your question. The strong urine that you sense your child has, is likely to be concentrated urine. Such concentration of urine is likely to occur due to prolonged periods without water intake. In normal circumstances such urine is found in all individuals towards early morning. Thus this finding of yours is most likely to be normal. Diabetes mellitus would present with increased urine frequency, increased thirst, increased hunger, loss of weight etc. If none of these are seen in your child, it is very unlikely that he would have the disease. Still in order to be sure you may get a urine sugar or a random blood sugar done. Also if you notice any associated symptoms like burning or pain while urination, fever etc. a medical consultation would be needed. If you have any more doubts, do write back.