Hi everyone! I have four broody ducks and they are all sitting on eggs but these eggs were beginning to get old so I decided to candle them! Before I could do so a duckling hatched and it's live and healthy at the moment! But there is one problem all the other eggs are now really old and haven't hatched! So I candled one of them and the egg was full of liquid so I smashed it and it was definitely off! But there was a dead duckling in it! What is the problem?