The basic laws of biology dictate that only one sperm can fertilize one egg. Once the sperm penetrates the ovum the chemistry of the ovum's cell membrane changes to prohibit any more sperm from getting in. Chicken hens have a place in their anatomy that can collect & store sperm for later use...
The hen was a Silver-Spangled Hamburg. A mid-sized hen, white with shiny black spots, and big dark eyes. Eight of the chicks were black with white lacing & had short legs, some of them feathered, like a bantam Cochin roo I have. Two were larger, black with white & with gold lacing, with...
This happened with a hen in my flock. She stole a nest and emerged 3 weeks later with 10 chicks. Eight of them looked like one of my bantam roos, but 2 others looked like the Americana roo. But they all had distinguishing features of the hen too, so I was certain the eggs were all hers. But...