I have gone through the history. It seems child was suffering with some kind of infection as fever
will not happen without infection. You have not mentioned whether fever is still there or not. Asssuming that fever is not there now. Sometimes post infection the child may have difficulty in digesting food items. In the above senario probiotics like Econorm
sachets and antisecretory medicines like Zedot baby sachets helps.
In food items you can try lactose free diet like Soya milk.