You would have noticed that whenever you are stressed or anxious, it possibly has a direct impact on your stomach as well – you could feel nauseous, have short-term diarrhoea, or have hard stool and be constipated.3 It is no different for children.4
The Vicious Cycle
However, here is the interesting thing. The source of your child’s refusal to poop could be his inability to poop. The variety of reasons could include any of these: he may feel self-conscious about going potty in his day care, he may be worried about making a mess, he may feel uncomfortable sitting on the potty, or he may just have witnessed another child being scolded for having an "accident" and may be worried the same will happen to him.5
The withholding of bowel movements leads to children passing hard and painful stools, and this in turn can make them refuse to go to the toilet. Children are fearful of the pain and do not want to repeat the experience, and therefore withhold bowel movements.
As you can see, at times it is difficult to pinpoint the exact cause of why your child starts to withhold bowel movements. However, whatever the initial cause, holding of stool leads to larger and harder stools, which lead to the child trying even harder to withhold the stool.
This then becomes a vicious cycle: