Hello and welcome to HCM, Mucus in a sticky proteinaceous substance secreted by the glands to the large intestine.ed mucus secretion is seen in infection with amoeba. However, amoebic infection is usually accompanied by detection of amoeba in stools. Greenish frothy mucus implies probably bacterial infection in the gastrointestinal tract. Staining while defecation shows that your child is suffering from constipation. Thus, constipation along with mucus and green colored stools means infection along with altered stool habits. You need to consult your pediatrician for prescription of medication. Thanks and take care Dr Shailja P Wahal