Our first five showed some physical differences at around eight weeks but you could tell male from female only by comparison with them side by side. The females' snoods were shorter, their faces were smaller and their general size fell behind that of the males. The boys spar and the girls ignore them. We didn't know how to vent sex so it was a matter of waiting. We had a bad ratio, though. Only two hens in that group!
We now have an additional four birds; one stag and three hens, all of them mature. The stag came along with his hen and she was playing hard to get. When the latest two arrived, he took to one of them in a big way. His original mate fanned and strutted and tried to get between them whenever they started their nonsense. The younger ones, having adopted the original hen as their mother, actually went on the attack. What a carry on!
