How soon before hatching do you hear the chicks peeping inside the shell?  I have 2 Buff Orpingtons sitting on eggs that I ordered and put under them on 5/13.   Tomorrow will be 21 days, but I don't hear any sound coming frome the eggs.  I candled them about 10 after I got them and all but 1 looked fertile.  I haven't candled them lately ,though.  Should I give them a couple of extra days since the were "mail order"?
	
		
			
		
		
	
				
			 
	 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
	
 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		