I just found an egg in nestbox that doesn't appear to be a chicken egg. It's round, white/beige, about 1 inch in size, dirty (my nest box is ultra clean!) I thought one of my girls had just laid a small egg and was going to break it open to see what was inside, but when I cracked the shell a bit (membrane not broken), it appears something is inside. I have no roos. Coop and run are enclosed, but a sparrow has gotten in the run a couple times in the past - Could it be a sparrow egg? Could it be viable? I feel horrible now about breaking shell. What should I do with it? Thanks for any feedback ... I'm new to posting, but am an addicted follower.