One of my chicks (born today from eggs simply sat on by hens, no shipping involved) seems to have an enlarged bottom and won't stand up. There's something blocking its vent but im not sure if it's the umbilical cord or pasty butt, so I'm afraid to completely wash it off. The vent doesn't seem to be off colored like most threads mention, but it is defiantly bigger than normal. Another chick also has the black crust on its vent but it can walk, but again still afraid to irritate anything on them. These are our first chicks so please help!