Well I doubt it is navel ill in a fresh-born calf. As many have said here... feel it and see if there is material inside. If there is, can you push the material back up into the body cavity? That would be a hernia, probably from a development issue, and not that uncommon. If you can push the guts inside up, I wouldn't be afraid to do that and band the extra skin as though banding a bull calf's nut sack. Just be sure you get all the "stuff" inside pushed up before you do it.