Low urine output can be due to various reasons, also depens on the weather and consumption of water. If she is refusing to drink due to fullness post meal that’s alright. Sometimes during/post recovery children might be irritable. otherwise refusal to drink at 18 months should be consulted by an expert.
See a paediatrician, not urologist.
Next Steps
They may ask you ro run some tests to check fucntion of
kidney. That’s alright.
Health Tips
Be observant of her breathing,solid food intake and toilet habits and communicate everything well to the doctor. Take care.