we have 2 billies, a 2yr old and a 3 yr old.
there are no problem and live together for most of the year, either in a large stable or in a field. they do lock horns but it always seems in jest than real aggression. they are just about to be separated and put with their own nannies for the winter. they have smelt the nannies over the fence and this hasnt brought on any aggression except high spirits. they have been all together with the nannies before and that wasnt any problem either. never any injuries.
they share with a little wether and are fine with him too.
mine are bagots so quite shy with humans so they wouldnt consider being rough with me, and arent really rough with each other.