I have two, 2 year old Isa Browns. I have two Silver Wyandotte chicks and 2 Amercaunas that were born on 8/18. When do I introduce them to my older 2? I also have 10 Cornish rocs chicks that were born on 8/18 as well but I'm pretty comfortable with what I need to do with them. All the chick's are currently residing together. I'm trying to decide at what age the 4 layers need to be introduced to my Isa's. I will gladly accept any advice.