I bought 4 ISA browns from our local feed store, believing that they were all girls, I think they all looked the same colour when we got them, the buff one was a little lighter, but not silver like a red sex linked male chick should be (I think!). Now at 5 1/2 weeks one of them looks way different than the other 3, which all look the same as my last ISA browns a few years ago. It is solid buff coloured with no brown on it and I think it's a boy, it's comb and wattles just seem too red and big. Is there any way it could just be a different breed? We really can't have roosters!