3 years old baby stool sour odor is mostly considered for indigestion and other gastrointestinal dysfunction, it is recommended that under the guidance of the doctor to take drugs to promote digestion. Under normal circumstances, 3-year-old baby’s stool 1 to 2 times a day, shaped, slightly odor, not dry are normal phenomenon. 3-year-old babies have the phenomenon of sour and smelly stools, accompanied by thick white tongue, bad breath and other symptoms, it is indigestion and other gastrointestinal dysfunction, you should follow the doctor’s instructions, take probiotics (such as Bacillus subtilis bacillus granules) and so on. You can also massage the abdomen clockwise to promote gastrointestinal peristalsis, and you need to drink more water to promote metabolism, and usually eat a light diet. If the above methods do not provide relief, then you need to go to the hospital for treatment, check the stool routine, under the guidance of the doctor for treatment. One of the causes of indigestion and other symptoms is due to the baby ate too much, over-nutrition, usually to develop a good habit of eating on time, quantitative eating, light diet, less spicy stimulation of indigestible food, more exercise, promote intestinal peristalsis. 3 year old baby sour stool may also have other causes, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment, the above medication as prescribed by the doctor.