Hello! I am new to chicken-keeping and am looking for some advice on introducing new birds. I've read a number of posts about older hens and new birds, but I'm not sure what to expect with my situation: I started with three baby chicks who are now about 12-13 weeks old. One of the "girls" turned out to be a boy, so he was just pulled out of the flock and two new pullets are replacing him. One is about 8 weeks old, and the other is about 10 weeks old. Initial introductions did not go well -- the older girls went after the new ones right away -- so they are separated for now. Last night, I put the two new ones in a dog crate to sleep, and today they are hanging out in the coop while the older ones are confined to the run. My questions are: What should I expect as I try to get them introduced to each other? Is the 8-week-old pullet going to be able to hold her own with the older (and bigger) ones? And any suggestions for how to introduce them? My plan was to keep them separated some now and only let them interact through the bars of the dog crate when they're not separated. I'm hoping I can get them through this in about a week or so, as I'll be heading out of town and leaving a "chicken sitter" to care for them -- don't want her to have to deal with all this if possible! Suggestions, advice, and thoughts are appreciated!