How difficult is it to introduce new chickens to a flock? And is it easier to do when chicks are still young instead of full-grown? Mine are 6 weeks and either this year or next, I'd like to add a couple more. Is there any difference if I were to add them now versus waiting till next year? I'd also like to add salmon favorelles which are supposed to be a very docile breed to my flock of 5 New Hampshire Red, Brown Leghorn, and Black Copper Marans. Is this a bad idea to add a docile bird in with these breeds?