I had two Birmingham Roller eggs abandoned because I didn't get the nest boxes in soon enough and the parent just laid the egg on the floor and left it. I put it in a egg carton and waited until the second egg was laid and then I put them both under a makeshift incubator. They have been incubating for 5 almost 6 days. Today one of the other pairs (West of England's) laid their first egg so I was wondering if I could put the Birmingham Roller eggs under them after they lay their second egg? Could they handle 4 eggs? I'd take care of the BR squabs after they hatch so it wouldn't overload the WOE pair. I know the eggs I've been incubating are alive because I candled them yesterday and I could see the embryo.