Foamy stools in infants may be caused by problems such as lactose intolerance, indigestion, or enteritis. 1. Lactose intolerance: Because the digestive system lacks the enzyme lactase, it is unable to break down lactose, which may lead to diarrhea accompanied by foamy stools. 2. Indigestion: When the diet contains too much sugar or fat, and the child’s digestive ability is relatively weak, it is easy to cause foamy stools. 3. Enteritis: Inflammatory reactions in the intestines due to various reasons can affect normal digestion and lead to changes in stool patterns and the appearance of foamy stools. Foamy stools in infants should be seen by a pediatrician at the hospital in a timely manner to identify the cause and then treat it under the guidance of the doctor, so as not to affect the child’s health.