I just completed my 55.5" osage bow but while tillering it I heard a small crack. When I inspected the back of the bow I found that a small sliver had popped up. I unstrung the bow and scraped and sanded the crack until it was relatively smooth. I guess my only option would be to back it with something. My question is will a paper bag backing do the trick? If not how about rawhide? I would prefer paper bag because it is so much easier to do but do not want my bow to break. Any suggestions?

I'd do a sinew wrap, on the splinter. Is there a need to do the whole bow?

I would sinew the whole bow.  But a wrap could take care of it.

I might sinew the whole bow. A paper bag would work but it might be a little ugly. For now I would put a dab of super glue and wrap it. If you want to put a backing on later you can take the wrap off. If it were my bow I would just super glue and wrap then do the same thing to the other side so it's symmetrical.