Two year old babies with loose stools may be caused by non-infectious factors or infectious factors (viruses, bacteria), etc. 1. Non-infectious factors: (1) Improper feeding: usually seen in artificial feeding, if a two-year-old baby is fed irregularly, overfed or consumes a lot of fat or starchy food too early, it may lead to loose stools. (2) Climatic factors: If the weather suddenly turns cold, the abdomen of a two-year-old baby may get chilled, which will increase intestinal peristalsis and lead to loose stools. 2. Infectious factors: (1) Viral infections: for example, rotavirus, after invading the intestinal tract of two-year-old babies, will destroy the impaired ability of the mucosa of the small intestine to absorb water and electrolytes, resulting in a large amount of intestinal fluid collecting in the intestinal lumen and leading to loose stools. (2) bacterial infection: such as Escherichia coli, Vibrio cholerae and other bacteria invade the intestinal tract of two-year-old babies will produce enterotoxin, which leads to diarrhea. Two-year-old baby dilute stool, there may also be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.