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Most likely the boys will not get along if there is a girl in the cage. Even though they're neutered, this does not change how they act. They still want to fight over which girl is theirs.
I'm not saying it is impossible for boy pigs to get along when girl pigs are involved, just it's more likely that they won't.\
Anyway, goodluck. I would maybe seperate on sex if bloodshed is a problem.