Last night I checked the chicks that hatched out 2 days ago. There were 9 out from the 12 I had under my girl and they were all moving around great and looking healthy. I removed the three unhatched and my son and I opened them and they were unfertile. This morning I went down with my coffee to check on them and when the mum came to me for some food I noticed a dead chick. It looks like it had been squashed. Is there anyway I can prevent this from happening again?