I have a hen that has gone extremely broody so I got a few green colored eggs (so I know which eggs to leave under her since all my girls lay brown eggs) from a friend and stuck them under her 4 days ago. She has been happily sitting on them and only leaves to eat and drink and them right back she goes. Yesterday when I went to check on her I noticed that one egg is gone. The only evidence left that it ever existed was some yellow yolk stuff on the other eggs. My guess is that she or one of my other hens ate, but my question is why??