Mam i would say of ur child is holding poops it indicates some fear in passing.it may b due to anal cuts bcz of passing hard stools.so get ur child examined.if so apply smuth ointment or make ur chils sit on luke warm water.
If constipation avoid junk foods give lot of fluids ,fibre rich diet and use medication only of doctor consultation.
Intestinal obstruction presents with not passing poops pain abdomen vomittings abd distension etc.
Next Steps
consult doctor for anal examination ,to know cause of constipation functional or organic and also to rule out sub acute intes obstruction which will often goes unnoticed for longtime.this may b any of these.