[Pippit's Mommy]

Not sure if this is normal, but I never noticed it on other dogs. Pippit has this little (feels like cartilage ) nubbin something or other right where his rib cage ends (meets) on the belly side. Doesn't seem to hurt or bother him whatsoever, nor can you even notice it by looking at him. I just feel it all the time when I pick him up, hold him, etc. Anyone know what this is? Should I take him to the vet?