At what age can Mama and chicks be introduced to the flock???

[Burleigh Chick]

I have a broody Brahma sitting on a clutch of eggs due to hatch in 5 days!!!

They are segregated in a nursery in the coop. I am wondering at what age I should be able to introduce the mama and babies (3 of my eggs look like they will hatch) into the general population. I have another hen who just went broody and would like to give her some eggs too, but I only have one nursery... I don't want to prematurely evict them and put the babies at risk........advice!!???????
thanks all