the most common cause of this event is what is called a toddlers diarrhoea , which Is an exaggerated physiology towards digesting carbohydrates, the color of stool isn t important and doesn t warrant workup . the bloating is because carbohydrate malabsorption and fermentation by bacteria in the colon can cause gases. don t worry this cindition is not serious all you need to do is giving him high fiber diet , eliminate chips and potatoes from diet , give more milk and decrease juices . I hope this helps