There is nothing to worry about. The common polyps in children are juvenile polyps that are usually single, do not need further workup and do not have any malignant potential. I suggest the following:
1. Have the pathology slide reviewed. It might be a simple juvenile polyp.
2. If your child has no further bleeding, nothing needs to be done
3. If bleeding recurs, then a colonoscopy is indicated. If it is not possible in Guwahati, then you may need to travel to Delhi
4. The alternate test is a good double contrast barium enema. But this may not pick up the very small polyps.
5. If it is true that your baby has lost 5 kg weight, then he needs to be seen; although this may have nothing to do with the polyp.