Please follow the following suggestions it might help.
1.Stop bottle feed if child uses it.
2.Stop any top milk if you are giving.
3.Continue with breast feed .
4.In case of top milk give him zerolac.
5.Give him thick rice water,pulses water, khichri,banana and yoghurt
6.Avoid wheat products.
7.continue with antibiotics for urinary infection.
Caution:contact your pediatrician
in case of dehydration