My chicks are 4 weeks old, can you tell by looking what sex they are? I have 4, 2 are RIR and 2 are Black Australorps, they may be mixed I'm not sure.I think this is a hen I think the red one is hen and the black one maybe a rooster. In the next 2 I think this red one is a rooster. The last pic. is the two together I think are roosters.