1. What is diarrhea in an 11-month-old baby? Diarrhea in an 11-month-old baby means that the baby\’s stool becomes softer than usual, even watery, and the frequency of defecation increases. This situation usually lasts for a period of time and will affect the baby\’s health if not treated in time. 2. What are the causes of diarrhea in 11-month-old babies? 1. Infectious diseases: including bacterial, viral and parasitic infections, such as gastroenteritis, diarrhea, etc. 2. Food allergy: Allergic reactions caused by certain foods may also cause diarrhea in 11-month-old babies. 3. Indigestion: If the mother does not pay attention to dietary hygiene problems during feeding, or