Four-month-old babies poop bubbles may be related to the addition of complementary foods, cold, intestinal infections and other reasons. 1. add supplemental food: because the role of 4 months of the baby part of the baby has to add supplemental food, some babies add supplemental food after indigestion, can also appear bubble-like stools. 2. cold: due to the cold stimulation of the abdomen, causing intestinal peristalsis accelerated, digestive disorders, some babies can appear with foam-like stools. 3. Intestinal infections: babies like to eat their hands or food is contaminated, etc., may cause intestinal viral or bacterial infections, resulting in intestinal inflammation, may appear foamy stools. Four-month-old babies poop bubbles can also be seen in other causes, such as lactose intolerance, it is recommended to consult a doctor in a timely manner, follow the doctor’s instructions for relevant examinations, in the doctor’s help to clarify the cause, and targeted treatment or therapy.