I am re-homing some baby chicks for a friend since I already had a few of our own. Mine are only 4 weeks and hers are 5-6 weeks. They have gotten alone perfectly for the past week but now one of the other chicks is being super aggressive. We split them up (ours and hers) but the one is still attacking the others from its own family. We have someone coming to take them on Saturday but I wanted to make sure that this was normal before I send them on their way. They are Mexican Bantams and it doesn't help that they seem to be a bit more nervous in personality and one is a screamer... anything makes it shriek! LOL! Thoughts?? Normal?