My little bantam is a mixed breed. Old English is in her blood, but not sure what else she is mixed with.
I have a mixed flock with bantams, polish, new Hampshire reds, a couple Easter Eggers, a lavender and golden orp, a sapphire, and some black sex links. So far, only the bantam and sex link are turning broody. (My mom is scared to check under them for any extra eggs. I think it's amusing since I'll reach under them without any problems besides the fussing and feather rustling).
I did find one of the hatchlings, but it looked like it was stuck to the sex links underside when she got off the nest. I found the dead chick still in the egg on the ground. There was another pipping when I checked. I did try to move them around and let the little bantam have her nest back and put the sex link on another fresh nest of eggs, but she booted the bantam off again. So, I switched out some smaller eggs (some bantam and a couple polish eggs) and let her have the Fresh nest since she hasn't been able to brood the last several days.
Honestly, I don't have a cage or separate space to house the broodies in, so I'm just having to let them do their thing in the yard. I'm also noticing the the milk crates aren't working out very well as a brooding nest but haven't been able to come up with something better yet. . .
I can hear the sex link fussing now and then out in the chicken house, so I'm assuming that the last couple eggs are trying to hatch. I suppose the chicks will have two mamas to protect them if they hatch. Lol
I am relieved to know that what they're doing is normal though. Thank you for clearing that up.