Welcome to healthcare magic....Hope you find the answers to your querries here....
Well, regarding your child, the lump palpable in the abdomen could be just a simple lipoma
!! Is the swelling present all the while or is it seen more prominently on straining?? It must not be anything significant most probably, but if it is associated with pain or increases in size on straining, it could very well be a hernia(contents of the abdominal cavity coming through a weakness in the abdominal muscle wall) which is reducible. Kindly reassess and get back to me if in doubt. I will be always available to answer your queries.Take care. bye.