Brief Answer: its due to patent vitello intestinal duct Detailed Answer: Hi, The thing is that during intrauterine development, the umblicus (belly button) is joined to the small intestine by what is called as vitello-intestinal duct. This duct usually closes before birth in most of us. But in some a part of it may remain patent, and in some the whole of it. The stool may be coming out through this patent duct. You need to show her to a pediatric surgeon for this. If found, this condition is surgically correctable easily. Hope that I have answered to all your queries. If you have further queries, i will be glad to answer them. Regards Dr. Ashish Verma

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