When my children was born the umbilical cord was cut and tied off. (((( Even when in hospital ...I made sure they did as we wanted... My first two was born at home though. ))))It took about a week or so before that little piece fell off of the belly and that piece was kept to put into the umbilical cord pouch. It was kept for good luck and good health, like a good luck charm for that child. It belonged only to that child, and when that person passed away, it was buried right along with them. It was something that was a tie between the mother and the family and the tribe as a whole .
Also some do make the necklaces from the dried cord and all sorts of colored seed beads would be added. Differebtt tribes did different things wado Annie
( ((((I still have mine ,in a leather pouch ,to go with me when its my time))))