Ok I have had this problem since before my first child was born she is now 39 years old this problem was not to bad at all to start with it would pop out and go back in without me pushing it back in. So when I GOT PREGEANT  with my children it did not bother me it never poped out but after I would have my children it would start to pop out and it would go back in but one day it poped out and I would have to push it back in  it is under my right rib cage before it would pop out and I would push on it and it did not seem to want to go back in BUT YES THANK GOD IT DID GO BACK IN!!!! when it pops out it feels like something hard about the size of a half a dollar I guess it will move around under my rib cage sometimes which feels like a baby when the baby kicks in your stomach which not that hard it fills a full feeling under my right rib cage it gets irrtated under there sometimes I have been having some problems with it recently right now it feels full kinda a tight feeling and kindda a burning sensation under there now. I had a ultra sound done on this under my right rib cage the doctor said nothing showed up praise the lord the doctor said we will just call it a floating rib. If you could give me some idea what this is I would appreciate it GOD BLESS YOU RICHLY IN JESUS ALMIGHTY HOLY POWERFUL NAME AMEN!!!!!!!!