Help me ID my 4 week old McMurray's exotic spare - she seems a wee bit smaller than all the rest, and her feathering is definitely delayed compared to the Whitings and the Barred Rocks. She has lots of feathers on her legs, less wing feathers than the others and almost no tail feathers at all. She seems too uniformly yellow to be a Buff Brahma. Her attitude is a docile, not outgoing like the Barred Rocks at all, or flighty as the Whitings. She's on the right, with a Whiting True Green pullet in the foreground and what I fear will be a Whiting True Blue cockerel to her left (he has wattles and no one else does). All chicks the same age.
Any ideas?