The seller thinks they might of hatched sometime in July. My rooster just started to crow last week and just today I've noticed him doing the mating dance! But the hen isn't ready yet so she'll run from him. Seller don't know which breed they are and said they could be mixed. He originally told me that they're miniature chickens but they've doubled in size since I got them in late Sept. to early Oct. sometime there. They're not small but not big either. So like Medium?