I have 2 hens that are about 9-10 weeks old. I started out with 4 but 2 ended up being roosters and I had to rehome them. I'd like to add a buff orpington or another rhode island red and have 3 hens. I'm just not sure exactly when to add a new bird. Should I wait until my 2 are older? Will adding a 3rd bird create problems? Will they get along? I appreciate any information - I am new to having chickens.