I don't really do brooders. Mum keeps them warm and safe. I don't let them sit when winter is coming. Mum does the integration and often shares the protection with the father.Oh dear.. could you pull the chicks and brood them in a brooder? Or is it more of a let nature take its course thing?
I just get in the way.

For the baby killers, I just don't let them sit any more.