This is my first year for keeping chickens. I got my first group of Columbian Wyandotte chicks in May so they are about 3 months old. I built a small coop that they go into at night. I also got a new group of mixed (beautiful) wyandotte chicks a couple weeks ago. I keep these 12 chicks in a brooder box at night, and move them to the coop all day while the five 3 month olds are out. The older girls can see all the chicks and antics (these chicks are wild and crazy...no kidding). I don't have a run built ( maybe this fall when it cools WAY down here). I just let my chickens run my small fenced back yard. So far no problem. Is this situation going to help any when I go to integrating the two flocks together?