Ok so I purchased two chickens from a farmer one as a young pullet and the other as a hen(or what I thought was a Hen). I have since figured out that the older one is actually a Roo. And now I am wondering how or when I will be able to tell if this pullet is a Roo or a Hen. Since this farmer didnt know he was selling me a 5month old Roo I am less than confident that he knew if this is a hen, or how old it was. How do I tell by age when she/he can join the other 3 6month old Hens?