in my flock of 18, i leave momma and babies right in the mix of it.... theres no re-introduction, which can be tuff..... they grow up as part of the flock, amazing how the little guys get right in there and steal treats from the adults.. my biggest surprise was how fast they are outside running around in 30 degree weather........ after a week or so of chick food where their nesting, i just put the entire flock on flock raiser feed and put oyster shell on the side....