A less serious, self-limiting case of melena can occur in newborns two to three days after delivery, due to swallowed maternal blood.
Children with Crohn's disease may suffer delayed development and stunted growth. The range and severity of symptoms varies.
Parents should be aware of their children's bowel movements and monitor the shape of poop to look for any consistent abnormalities. If children have unusual poop colors or even hematochezia (red poop) you may want to consult a medical professional. The two colors of poop to watch out for are red (blood) or black (caked blood). Green poop is ok as it is often due to having eaten some vegetables.
Additionally, since children tend to play in unclean environments, try to make sure they do not come into contact with any type of feces because feces can carry parasites and bacteria from a person's or animal's infected intestines.
Many young babies who are still breastfeeding do not have a fully developed metabolism. Their bodies do not metabolize red blood cells. In healthy adults or children, the byproduct of red blood cell metabolism is something called Bilirubin. Bilirubin is responsible for giving human feces the common brown color. Since babies do not metabolize enough red blood cells, they do not produce enough Bilirubin, and thus their poop is often green or yellow color. First time parents get a little bit scarred by this, but it is a normal occurrence.