Your son has passed brown blood in stool and is having pain in the stomach?

Depending on his age it may be an anal fissure from passing hard stools. If it's just slight streaking it may be from constipation. If it's quite a bit or very often I would get him checked out right away. Maybe try some juice and veggies to see if this helps. Also drinking lots of water.

Hard bowel movements can cause blood to show up in their stool. Also, depending on his age, he may be "poking around" down there as a form of stimulation/masturbation. One of my adolecent charges scared me one day when it was noticed that his testicles, penis and anus were very red and he had some blood in his stool. His mother and I thought he was being sexually assaulted during his day program. After a trip to the emergency room, It was concluded, with help from the child, and the doctor, that he was "discovering" himself, and masturbating quite enthusiastically, quite often. What a relief! Blood in a child's stool MAY be a sign of sexual abuse, or it could be a sign of passing a very hard bowel movement. Keep an eye on his B.M.s and also speak to him. It could be non-serious, but it could also be a harbinger of something inappropriate. If it persists, I would have him seen by a doctor.

It could also be caused by a blockage or polyp. My son had bright red blood when he had bowel movements for over a year. The doctor said it was probably just very small anal fissures. He also had very frequent, smelly gas and his bowel movements were small and thin, instead of the usual long and round. The polyp finally broke off the 'stem' that was anchoring it to his intestines and he passed it while on the toilet. We took it to the doctor, where they tested it and said yes it was a polyp. They said the blood was from his stool pushing against it, causing it to pull away from the wall of his intestine. After he passed it he had no further bleeding, stools became a normal color/shape and he no longer passed gas.