I have a rooster who is 12.5 weeks old. I have noticed that for at least 2 weeks he often stops and then just slumps over to one side (not always the same side). If I walk up to him he will pop right up and walk away so I have figured he was sunbathing. This morning, I let them out of the run to free range he seemed to spend even more time lying on his side. He can get up if you touch him but would also just lay there and let you pet him for a minute before he decided to get up. This afternoon, I noticed that he was favoring his left foot. If I pick him up to put him on my lap, when he flaps down he lands poorly and pretty much falls forward. I don't see any wounds or scabs on his legs or feet. No swelling anywhere or loose scales. I don't see any bugs. The 5 hens are all fine. I went out to go check on him and his is not sleeping on the roost like usual but is sleeping on the floor of the coop instead but still seems alert and otherwise fine. He eats (chick crumbles still as well as appropriate kitchen scraps and whatever he can find in the vegetable garden) and drinks without difficulty. Normal poos. He seems to be otherwise Ok. It is almost like he has a sprained ankle or something but I can't see any injury and he hasn't had any trauma. I don't medicate them (except what's in the crumbles) and haven't done anything in particular. Should I be doing anything? Do I need to separate him from the hens (they aren't bugging him so it would be in case he's contagious I guess) and if so, can it just be a dog crate in the pen or does he really need to be separate?