Hi. I have two chickens I want to introduce to the flock. I have raised them from 1 week in a brooder and they are now about 6 weeks old, about a month and a half younger than the others. I plan on putting the two inside the run in their own “look but don’t touch” area. My question is how long should I keep them in there? They r about half the size of the others but fully feathered.