This is usually due to a Congenital Umbilical Hernia and is extremely common. It is caused by a failure of the muscles in the wall of the abdomen to ''fuse'' completely before the child is born. As a result a bit of the bowel may protrude, and this becomes more obvious when crying or straining. Most umbilical hernias close by age 4-5 years. If this does not happen, surgery is required.
DO NOT ''band down the navel'' NOR should we tape it down with the ''old-time willie-penny''-------This can have serious ill-effects.