I have 2 Rhode Island Reds about 7-8 mos old and 2 young pullets (Ameraucana & Wyandotte) that joined the older hens in mid-July. The 2 hens had been laying almost daily, but one stopped as soon as the new arrivals moved in. Now it is the end of Sept. and this hen has not laid another egg. In comparison to her partner hen she seems weaker and can no longer jump/fly up to the usual nighttime roosting spot, having to climb into a nesting box about 6" off the ground instead. Her comb is drabber & floppier than the other RIR and she seems to have runny poop at times. When I pick her up she is MUCH lighter than the other of the same age & breed. Yet she doesn't actually seem sick, still eats well and runs around when I let them all out to free-range each evening. Given the above info, could something be wrong with "Ethel"? Thanks for any advice!