In another post I mentioned that my broody Silkie had been pushing several eggs away, that I kept putting back under her. They were always cold, but I put them back anyway. The last time she did it I put them in the incubator. Several days later one of them hatched. Several days after that another one hatched. Then the ones that she kept, hatched. I still had one in the incubator that I had kinda forgotten about. I finally looked at a calendar and realized that the egg was at least 26 to 29 days old, had been cold numerous times, and I had better throw it out before I had a stinky mess to clean up. The next morning I went to do just that and found that it was pipping. A few hours later I had a brand new Silkie chick! After it dried I noticed that it seemed like it had a thicker and longer feathering than most of my others have had. Maybe that was because it had gotten cold . I have never had one take that long.