Diarrhea after constipation in a 2 year old child may be caused by bad dietary habits, mental and psychological factors, indigestion and other reasons. 1. Bad eating habits: If a 2-year-old child always eats some indigestible food, and eats too cold or stimulating food, it may lead to the child’s constipation followed by diarrhea. 2. mental psychological factors: if the 2-year-old child mood fluctuations, or the existence of nervousness, anxiety and other emotions, may lead to gastrointestinal dysfunction, so that the 2-year-old child constipation followed by diarrhea. 3. indigestion: if the child over-eating, resulting in the accumulation of food in the gastrointestinal tract, gastrointestinal function abnormalities, may also lead to 2-year-old children after constipation diarrhea. 2-year-old child diarrhea after constipation, there may also be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.