Even though they are brothers, this does not necessarily mean they will get on.
The boars being next to the sows could also be an issue as the boys get older and their hormones are raging.
I think the accepted way to keep boars and sows i the same room is to have the boars on top and the sows underneath, but I am sure someone with more experience will correct me if I am wrong.
How big is their cage (as in the actual measurements)?
And do they have 2 of everything (bottles, houses, food bowls, etc)?
If they have already fought and blood has been drawn then sadly thy may not be abel to love together again.
You can always try re-bonding them in a neutral area though.
There is an excellent guide to this here:
Boars: Bullying, Fighting, Fall-outs And What Next?
Good luck with everything - they can be very opinionated when the mood takes them!