I had just 4 Barred Rocks but unfortunately lost two of them quite suddenly. Both to injury not illness. I immediately went out and got 3 more Barred Rock chicks which are now right at 5 weeks old. My two older girls seem quite out of sorts. Is it too soon to introduce my little ones. I really think the older hens are upset that it is just the two of them. They are both very easy going birds.