My two cochins are the same age and one is bigger than the other. The little one has poop on his but all the time and i think this is what u call pasty but. Is this bad for the chick, and is she stopped up? Is this why she is smaller than my other one? How do i fix this? This is the chick my son picked out and they are already big buddies, he named it dinasor. I would hate it for him if it died. Please help.