I have read a couple of older threads about inbreeding and linebreeding including this one, https://www.backyardchickens.com/forum/viewtopic.phpid=224917&p=3 which was very helpful but doesn't directly answer my question. I want to know whether accepted "safe" breeding practices for chickens include breeding half siblings to one another. Is this asking for trouble? I really have no experience with breeding terminology, so please spell it out for me if you can. Does "line breeding" include only parents to children/grandchildren?