I’ve got 3 cockoo maran chicks, and I read the rooster will show signs early on by lighter feathers. They were supposed to be sexlinked at tractor supply, but I’m suspecting one is a rooster. Here are pics of two of the cockoo’s…. As you can see the comb is more pronounced also on the one I think is a rooster. I believe they were pretty new born when I bought them, maybe a couple days old, that was about 3 weeks ago. So I’d say at most 4 weeks old?