2 days ago I got 3 younger pullets who are Millie Fleur Cochin Bantams and added them to my flock of 14 girls who are about 3 weeks - 8 weeks old. I added them at night and the "big" girls are so mean to my "little" girls. They wont let the littles get to the water sometimes, if they are outside, wont let them back into the coop. How do I get the big girls to play nicely with my little girls?