I had 2 brothers from my litter last year together and all they did was fight but not to bad untill they got abit older then 1 ripped of the others ear and gashed his head so i split them up. I sold the 1 that got injured and kept the other 1 he is now in with 3 other boys and there all getting along great. Its a chance you have to make if it dont work then just seperate them.