"In a few weeks" - 2 weeks would be a general guideline. It's not so much about the age of the littles but more the older birds getting used to their presence. So what I like to look at is how the hens are reacting... if the older birds can routinely walk by the chick area without much interest, that's a good time to try and schedule for face to face introductions.
They spent two nights together thus far and I let them roam the backyard together. The one big girl that attacked them, ignored them some until littles got close and then she ran after them and pecked one and pulled a feather out. I will give it time. I just hate for 3 little girls to be in a dog cage all day. But it’s only for a few weeks. Such interesting little creatures. Thanks everyone
2 nights is no where near enough time. You'll need to make sure your coop and run are also bigger than the recommended minimum. Integration needs time and space.
I plan on keeping them physically separated for at least two weeks but have been allowing them to roam in my big backyard supervised. I am making sure my littles are always in a place they can’t get cornered. They keep their distance from big girls and fort the most part the big girls ignore them.
