Can a hen lay eggs within a week period and one egg be from Roo #1 and one egg be from Roo #2? I don't know why, but I thought the sperm stayed in there for a few weeks by one roo and just assumed that another roo could not fertilize her ... well, he COULD but I just assumed the eggs would all be fertilized by the sperm that was there first. Did that make sense? LOL Anyhow, I have chicks hatching and one of them is very obviously a chick from my colcorful mutt rooster ... who had NOT been in that pen for over 30 days. So, I was shocked to see a chick that he obviously sired.