You really are having a difficult time.The average weight for a boy of 2 and a half is 13.3kg. Your son's weight is on the 10th percentile line of the children's growth chart;the lowest 10% for boys of his age.I don't have to tell you that he should be drinking much more than he does.Your son needs at least 1litre plus 50ml for every kilogram he weighs above 10 kg. This means that he needs 1000ml+ 50ml +40ml [for the .8kg]=1090ml per day.The only advice I can give you is to contact the gastroenterologist who saw your son originally so that a decision can be taken about helping your son.
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