I have six Brahma chicks that are around six weeks old. They were getting too big for their brooder as well.. I took my layers out of the layer coop and put the six-weekers in with Broody Brahma and her three 3-wk-old chicks. Figured she would teach them chicken manners in short order.
So far my assumption has been correct; the big kids stay in one corner and broody/chicks go wherever they want.
They walk a very straight line around her and I think by the time they come of size they will fit in just fine with the adult brahmas. 
So far my assumption has been correct; the big kids stay in one corner and broody/chicks go wherever they want.

