It may be normal for a three-month-old child not to poop for two days. However, it may also be caused by constipation, intestinal obstruction and other diseases, which are abnormal phenomena. The digestive function of a three-month-old is still not well developed, and the bowel movement cycle is not stable, so the phenomenon of not pooping for two days may occur. If the shape and color of the stool are normal, and there are no symptoms such as bloating or loss of appetite, this is generally normal. Children who drink too little milk or suffer from indigestion may be constipated, or have congenital megacolon or intestinal obstruction, etc., which may lead to the child not having a bowel movement for two days, which is generally abnormal, and prompt medical treatment is recommended. If a three-month-old child often does not poop for two days, he or she should consult a doctor and make adjustments as soon as possible to avoid adverse consequences.