Gray stools in babies may be related to dietary factors, congenital biliary atresia, gallbladder disease, etc. The specific analysis is as follows: 1. Dietary factors: when the baby has changed the milk powder or added complementary food, it may cause abnormal stools and the phenomenon of gray stools. 2. Congenital biliary atresia: if the baby is a newborn and pulls gray stools, it may be congenital biliary atresia, lack of bile, can not digest lipids well, causing gray stools. 3. Gallbladder disease: Babies with gallbladder disease, such as cholecystitis, may also have gray stools. Gray stools may also be related to other causes, it is recommended to go to the hospital in time for relevant examinations, to clarify the cause of the disease and treat the symptoms.