I have 2 barred rock pullets that are almost 4 weeks old and 2 Ameracuana's that are almost 3 weeks old. One of the Ameracuana chicks is significantly smaller than her sibling even though they are the same age. The other chicks are much more coordinated and chase bugs around the yard when I let them out but little Blonde just stays in the carrier most of the time. She walks fine and acts normal for a chick her size but she just isn't growing like the rest. I had been using unmedicated feed until a few days ago when I got nervous she might be sick so I switched to medicated starter/grower. One of the barred rocks and her sister Ameracuana had pasty butt a while ago but they are growing fine. Maybe she is just a late bloomer? What do y'all think?