Difficult to say without examination. There are various systemic diseases that can lead to mucous in the stool. This can include various causes of malabsorption - including celiac disease or fat malabsorption. Lactose intolerance can cause loose bowel movements. There are also cases of chronic pancreatitis that can lead to mucous-like substances in the stool.
You can consider blood tests looking for pancreatitis or celiac disease. Stool samples can be obtained an analyzed for possible causes of malabsorption.
If the symptoms continue, one can consider endoscopy for further evalation. This normally is done in conjunction with a pediatric gastroenterologist.
You can discuss these options with your personal physician.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
http://www.straightfromthedoc.com