The last chick of the batch had pipped, but wasn't making further progress, so we helped it out of the shell. Lo and behold, there was a second, much smaller chick in the other end of the shell, in its own sac. It hadn't had room enough to move and pip, so it suffocated, which was probably a good thing. It had been so tightly packed that its legs and feet were deformed... it never would have walked. The survivor's feet were ok, but one leg was permanently extended backward. We tried to straighten it, but weren't successful, so we had to put it down. This is the first time I've had a double-yolk egg develop, and it didn't turn out well. I'm going to be more careful about culling the double-yolks from the incubator in the future. Kathy, Bellville TX www.CountryChickens.com PS: I should have taken a picture, but didn't.