if the smaller one's are banty's then they will be able to hold there own in a fight i have banty's and standard's free range together during the day the hens probably wont do much damage to one another but the rooster's will probably fight until they determine who's the boss espacially with your rooster's they are a not so fighty breed if my roo's got at one another they'd probably kill each other but that's just because i raise game chickens and oeg's