Fully agree with Frederick. We had 2 males and 2 females and the two males did not get along and neither did the two females.  We had a decent size yard at the time but I suspected that if they had a flock to guard and acres to roam they would be better. So, either way if you have to of the same sex in a confined area without a job they will challenge for leadership and you will have some serious altercations.  This is the hard part for most owners - if two of them start fighting you are best to keep the others (if any) out of it and observe. They will typically end the scuffle by them selves if one submits. The danger is if there is no submission. What every you do - never get between them when they are engaged. You can before.