Here is some recent photos. They are now about 4 1/2 months old. The big one has started growing a comb and waddles and it seems as he may be getting his saddle feathers in soon. He also has a bright red face and looks more "manly". I believe he is the rooster. He doesn't crow but stands more tall than the other one. The little one hasn't grown much and hasn't grown any waddles or a comb. I am hoping it is a pullet but still might be too early to tell.
do i keep us posted. i was thinking my lavender was a cockerel, but it looks a lot like your little one. mind you it is only 5 weeks... i shall try to be patient! the black orpingtons i've got are a lot easier to peg.
The big one is definitely a rooster. He stands tall all the time and has tried to crow one time. He is scared of all our hens right now but still has more growing to do.