One and a half year old baby three or four days a stool, if the baby did not cry when the stool, the baby stool traits are normal, then it is normal, if the baby’s stool is dry, then the baby may have constipation, which is abnormal, need to be improved through diet, medication and so on. One and a half year old babies generally defecate once a day, the longest should be 2~3 days to defecate once, three or four days a stool time is a bit long, if the baby’s mental state, diet is normal, no crying when the stool, the stool is also normal in character, then it is normal. There is no need to intervene. If the baby’s bowel movements appear dry and difficult to solve, hard as sheep’s poop grains, but also to observe whether there is pain during defecation, crying performance, if there are the above symptoms, it means that the baby occurs constipation, which is not normal. At this time, parents can use the open plug to help the baby defecation, but also to help the baby to improve the diet structure, more to the baby to eat some rich in dietary fiber vegetables, fruits, such as celery, spinach, bananas, dragon fruit and so on. You can also take oral medication such as Bacillus subtilis dictyostelium to regulate intestinal flora, and Bohol Oral Liquid to aid digestion to help relieve symptoms. If your one-and-a-half year old baby is experiencing symptoms of bowel movements once every three or four days, we recommend prompt medical attention. The above medications should be used according to medical advice.